Android 使用小技巧之 ：new Handler().postDelayed() 延迟intent跳转

最新推荐文章于 2019-08-16 16:46:41 发布
转载 最新推荐文章于 2019-08-16 16:46:41 发布 · 548 阅读 · 0

本文介绍了一个简单的Android应用程序中实现页面跳转的方法。通过创建一个Runnable对象并使用Handler来延迟执行页面跳转，同时在跳转后关闭当前页面。
 Runnable r = new Runnable() {
@Override
public void run() {
// TODO Auto-generated method stub
startGoPage();
}
};

new Handler().postDelayed(r, 2000);//延迟两秒钟把跳转页面finish掉

=------------------------=

startGoPage()｛
Inent intent = new Inent(xx.this,xxx.class);
startActivity(intent);
finish();
｝
new Handler().postDelayed() 延迟intent跳转
村头那抠脚大叔的专栏
02-18 2万+
//延迟两秒跳转 new Handler().postDelayed(new Runnable() { @Override public void run() { Intent intent=new Intent(MainActivity.this, Leansons.class); startActivity(intent); } }, 20
Android语言基础教程（71）Android高级用户界面设计高级组件之幻灯片式图片浏览器：别让你的App相册丑到哭！Android幻灯片浏览器打造指南，附祖传优雅代码
jxf_jxfcsdn的博客
11-07 892
想让你App里的图片轮播像淘宝首页一样丝滑？这篇指南带你深度拆解Android高级UI组件——幻灯片式图片浏览器。我们将从ViewPager2的底层原理讲起，结合Glide图片加载优化、无限轮播魔法和页面指示器联动，彻底告别卡顿和内存泄漏。文章包含一行行敲出来的完整示例代码，涵盖自动播放、点击放大等实用功能，保证让你的应用颜值飙升，用户再也不会因为糟糕的图片体验而秒退应用！
关于new Handler().postDelayed()
daozhongyang的专栏
07-29 1万+
new Handler().postDelayed(new Runnable() {    @Override    public void run() {     }   }, 800);   经本人做项目中反复验证   此方法会引起屏幕刷新，因此常用于启动页面的进度条刷新， 其他页面慎用
new Handler().postDelayed(new Runnable(){})
centor的博客
12-21 8450
new Handler().postDelayed(new Runnable(){})是运行在主线程里的 这个开启的Runnable()接口会在这个Handler所依附线程中运行，而这个Handler是在UI线程中创建的，所以 自然地依附在主线程中了,且new Handler().postDelayed(new Runnable())没有重新生成新的 New Thread（）. ...
android new Handler().postDelayed() 延迟intent跳转
Crystal_xing的专栏
06-07 1525
//延迟两秒跳转   new Handler().postDelayed(new Runnable() {            @Override      public void run() {          Intent  intent=new Intent(MainActivity.this, Leansons.class);          startActivity(intent
Android 简述： new Handler().postDelayed() 延迟intent跳转
u013758456的专栏
12-22 1300
今日遇到伟人降临人间的历史时刻，曾经的历史画面历历在目。 预想今日 延迟启动 大有人疑惑不解，故 特此神圣时刻 简述。 一般在遇到 过度欢迎界面的问题上，使用延迟 跳转比较 合理， 但 个人感悟，短暂的停留 利用遮罩层 ，时间到 隐藏之。。。。 //延迟两秒跳转   new Handler().postDelayed(new Runnable() {            
那现在MapFragment代码如下：package com.example.bus.ui.map; import android.Manifest; import android.content.Context; import android.content.Intent; import android.content.pm.PackageManager; import android.os.Bundle; import android.os.Handler; import android.os.Looper; import android.text.Editable; import android.text.TextWatcher; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.view.inputmethod.InputMethodManager; import android.widget.ArrayAdapter; import android.widget.Toast; import androidx.annotation.NonNull; import androidx.core.app.ActivityCompat; import androidx.core.content.ContextCompat; import androidx.fragment.app.Fragment; import androidx.recyclerview.widget.LinearLayoutManager; // 👉 新增导入：用于动态修改约束 import androidx.constraintlayout.widget.ConstraintSet; import androidx.constraintlayout.widget.ConstraintLayout; // 🔺 新增导入：用于设置 Marker 颜色 import com.amap.api.maps.model.BitmapDescriptorFactory; import com.amap.api.maps.AMap; import com.amap.api.maps.CameraUpdateFactory; import com.amap.api.maps.MapView; import com.amap.api.maps.UiSettings; import com.amap.api.maps.model.LatLng; import com.amap.api.maps.model.Marker; import com.amap.api.maps.model.MarkerOptions; import com.amap.api.maps.model.MyLocationStyle; import com.amap.api.services.core.LatLonPoint; import com.amap.api.services.core.PoiItem; import com.amap.api.services.poisearch.PoiResult; import com.amap.api.services.poisearch.PoiSearch; import com.amap.api.services.help.Inputtips; import com.amap.api.services.help.Tip; import com.amap.api.services.geocoder.GeocodeSearch; import com.amap.api.services.geocoder.RegeocodeQuery; import com.amap.api.services.geocoder.RegeocodeResult; import com.example.bus.R; import com.example.bus.RoutePlanActivity; import com.example.bus.ResultAdapter; import com.example.bus.databinding.FragmentMapBinding; import java.util.ArrayList; import java.util.List; // ✅ 新增导入 import android.view.inputmethod.EditorInfo; public class MapFragment extends Fragment implements PoiSearch.OnPoiSearchListener, GeocodeSearch.OnGeocodeSearchListener { private FragmentMapBinding binding; private MapView mapView; private AMap aMap; private Inputtips inputTips; // 数据 private List<PoiItem> poiList = new ArrayList<>(); private ResultAdapter adapter; private PoiSearch poiSearch; // 当前阶段：1=选择起点, 2=选择终点 private int selectionStage = 0; // 缓存已选 POI private PoiItem selectedStartPoi = null; private PoiItem selectedEndPoi = null; private Marker startMarker = null; private Marker endMarker = null; // 缓存关键词 private String lastStartKeyword = ""; private String lastEndKeyword = ""; // ✅ 当前城市 private String currentCity = "全国"; private static final int LOCATION_PERMISSION_REQUEST_CODE = 1001; // ✅ 标记是否已居中我的位置 private boolean userHasInteracted = false; // ✅ 反地理编码 private GeocodeSearch geocodeSearch; // 【关键新增】保存定位得到的“我的位置” private double myCurrentLat = 0; private double myCurrentLng = 0; private boolean isLocationReady = false; // 定位是否完成 @Override public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { binding = FragmentMapBinding.inflate(inflater, container, false); View root = binding.getRoot(); mapView = binding.mapView; mapView.onCreate(savedInstanceState); initViews(); setupMap(savedInstanceState); setupSearchSuggestion(); // 包含输入建议、防抖、回车事件 return root; } private void initViews() { adapter = new ResultAdapter(poiList, this::onPoiItemSelected); binding.resultList.setLayoutManager(new LinearLayoutManager(requireContext())); binding.resultList.setAdapter(adapter); binding.mapSearch.setOnClickListener(v -> performSearch()); binding.btnSwitchTarget.setOnClickListener(v -> { if (selectionStage == 1) { showEndpointSelection(binding.mapInput2.getText().toString().trim()); } else if (selectionStage == 2) { showStartpointSelection(binding.mapInput1.getText().toString().trim()); } }); binding.btnGoTo.setOnClickListener(v -> { if (selectedStartPoi != null && selectedEndPoi != null) { Intent intent = new Intent(requireContext(), RoutePlanActivity.class); intent.putExtra(RoutePlanActivity.EXTRA_SOURCE, RoutePlanActivity.SOURCE_FROM_MAP_DIRECT); intent.putExtra("start_lat", selectedStartPoi.getLatLonPoint().getLatitude()); intent.putExtra("start_lng", selectedStartPoi.getLatLonPoint().getLongitude()); intent.putExtra("target_lat", selectedEndPoi.getLatLonPoint().getLatitude()); intent.putExtra("target_lng", selectedEndPoi.getLatLonPoint().getLongitude()); intent.putExtra("target_title", selectedEndPoi.getTitle()); startActivity(intent); } else { Toast.makeText(requireContext(), "请完成起点和终点的选择", Toast.LENGTH_SHORT).show(); } }); } private void performSearch() { String startKeyword = binding.mapInput1.getText().toString().trim(); String endKeyword = binding.mapInput2.getText().toString().trim(); if (startKeyword.isEmpty()) { Toast.makeText(requireContext(), "请输入起点", Toast.LENGTH_SHORT).show(); return; } if (endKeyword.isEmpty()) { Toast.makeText(requireContext(), "请输入终点", Toast.LENGTH_SHORT).show(); return; } // 智能判断跳过搜索 if (startKeyword.equals(lastStartKeyword) && endKeyword.equals(lastEndKeyword) && selectedStartPoi != null && selectedEndPoi != null) { binding.btnGoTo.performClick(); return; } // 展示 UI binding.containerResultList.setVisibility(View.VISIBLE); binding.buttonGroup.setVisibility(View.VISIBLE); // 动态压缩地图区域 ConstraintSet constraintSet = new ConstraintSet(); constraintSet.clone((ConstraintLayout) binding.getRoot()); constraintSet.connect( R.id.map_view, ConstraintSet.BOTTOM, R.id.container_result_list, ConstraintSet.TOP, 0 ); constraintSet.applyTo((ConstraintLayout) binding.getRoot()); userHasInteracted = true; // 隐藏软键盘 View currentFocus = requireActivity().getCurrentFocus(); if (currentFocus != null) { currentFocus.clearFocus(); InputMethodManager imm = (InputMethodManager) requireContext().getSystemService(Context.INPUT_METHOD_SERVICE); imm.hideSoftInputFromWindow(currentFocus.getWindowToken(), 0); } // 执行搜索 if (!startKeyword.equals(lastStartKeyword)) { lastStartKeyword = startKeyword; lastEndKeyword = endKeyword; showStartpointSelection(startKeyword); } else if (!endKeyword.equals(lastEndKeyword)) { lastEndKeyword = endKeyword; showEndpointSelection(endKeyword); } else if (selectedStartPoi == null) { showStartpointSelection(startKeyword); } else { showEndpointSelection(endKeyword); } } // ✅ 显示“搜索起点中...” private void showStartpointSelection(String keyword) { selectionStage = 1; binding.btnSwitchTarget.setText("前往选择终点"); binding.btnGoTo.setEnabled(false); binding.emptyView.setText("🔍 搜索起点中..."); binding.emptyView.setVisibility(View.VISIBLE); binding.resultList.setVisibility(View.GONE); doSearch(keyword); } // ✅ 显示“搜索终点中...” private void showEndpointSelection(String keyword) { selectionStage = 2; binding.btnSwitchTarget.setText("回到选择起点"); binding.btnGoTo.setEnabled(false); binding.emptyView.setText("🔍 搜索终点中..."); binding.emptyView.setVisibility(View.VISIBLE); binding.resultList.setVisibility(View.GONE); doSearch(keyword); } private void doSearch(String keyword) { if (keyword.isEmpty()) return; PoiSearch.Query query = new PoiSearch.Query(keyword, "", currentCity); query.setPageSize(20); query.setPageNum(0); // ✅ 使用缓存的位置（仅当真实定位完成后） if (isLocationReady) { LatLonPoint lp = new LatLonPoint(myCurrentLat, myCurrentLng); query.setLocation(lp); // 让高德根据“我在哪”智能排序 } try { poiSearch = new PoiSearch(requireContext(), query); poiSearch.setOnPoiSearchListener(this); poiSearch.searchPOIAsyn(); } catch (Exception e) { e.printStackTrace(); Toast.makeText(requireContext(), "搜索失败", Toast.LENGTH_SHORT).show(); } } private void onPoiItemSelected(PoiItem item) { LatLng latLng = new LatLng(item.getLatLonPoint().getLatitude(), item.getLatLonPoint().getLongitude()); if (selectionStage == 1) { if (startMarker != null) { startMarker.remove(); startMarker = null; } startMarker = aMap.addMarker(new MarkerOptions() .position(latLng) .title("起点：" + item.getTitle()) .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN))); selectedStartPoi = item; aMap.animateCamera(CameraUpdateFactory.newLatLngZoom(latLng, 14f)); updateGoToButtonState(); } else if (selectionStage == 2) { if (endMarker != null) { endMarker.remove(); endMarker = null; } endMarker = aMap.addMarker(new MarkerOptions() .position(latLng) .title("终点：" + item.getTitle()) .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED))); selectedEndPoi = item; aMap.animateCamera(CameraUpdateFactory.newLatLngZoom(latLng, 14f)); updateGoToButtonState(); } userHasInteracted = true; } private void updateGoToButtonState() { binding.btnGoTo.setEnabled(selectedStartPoi != null && selectedEndPoi != null); } @Override public void onPoiSearched(PoiResult result, int rCode) { if (rCode == 1000 && result != null && result.getPois() != null && !result.getPois().isEmpty()) { List<PoiItem> newPoiList = result.getPois(); poiList.clear(); poiList.addAll(newPoiList); if (adapter == null) { adapter = new ResultAdapter(poiList, this::onPoiItemSelected); binding.resultList.setLayoutManager(new LinearLayoutManager(requireContext())); binding.resultList.setAdapter(adapter); } else { adapter.notifyDataSetChanged(); binding.resultList.scrollToPosition(0); } binding.emptyView.setVisibility(View.GONE); binding.resultList.setVisibility(View.VISIBLE); // 先设置 Adapter 的选中状态（触发 UI 高亮） adapter.setSelected(0); // 自动选中第一个 onPoiItemSelected(poiList.get(0)); } else { if (selectionStage == 1) { binding.emptyView.setText("⚠️ 未找到相关起点"); } else if (selectionStage == 2) { binding.emptyView.setText("⚠️ 未找到相关终点"); } binding.emptyView.setVisibility(View.VISIBLE); binding.resultList.setVisibility(View.GONE); } } @Override public void onPoiItemSearched(PoiItem item, int rCode) { // 必须实现 } private void setupMap(Bundle savedInstanceState) { mapView.onCreate(savedInstanceState); aMap = mapView.getMap(); if (aMap != null) { initMapSettings(); } else { new Handler(Looper.getMainLooper()).post(() -> { aMap = mapView.getMap(); if (aMap != null) { initMapSettings(); } else { waitAMapReady(); } }); } try { geocodeSearch = new GeocodeSearch(requireContext()); geocodeSearch.setOnGeocodeSearchListener(this); } catch (Exception e) { e.printStackTrace(); } } private void waitAMapReady() { new Handler(Looper.getMainLooper()).postDelayed(new Runnable() { int retry = 0; @Override public void run() { if (mapView == null) return; aMap = mapView.getMap(); if (aMap != null) { initMapSettings(); } else if (retry++ < 30) { new Handler(Looper.getMainLooper()).postDelayed(this, 100); } } }, 100); } private void initMapSettings() { UiSettings uiSettings = aMap.getUiSettings(); uiSettings.setZoomControlsEnabled(true); uiSettings.setCompassEnabled(true); uiSettings.setScrollGesturesEnabled(true); uiSettings.setMyLocationButtonEnabled(true); new Handler(Looper.getMainLooper()).post(() -> aMap.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(39.909186, 116.397411), 10f)) ); enableMyLocationLayer(); } private void enableMyLocationLayer() { if (aMap == null) return; if (ContextCompat.checkSelfPermission(requireContext(), Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { MyLocationStyle myLocationStyle = new MyLocationStyle(); myLocationStyle.myLocationType(MyLocationStyle.LOCATION_TYPE_LOCATION_ROTATE_NO_CENTER); aMap.setMyLocationStyle(myLocationStyle); aMap.setMyLocationEnabled(true); AMap.OnMyLocationChangeListener listener = location -> { if (location != null && !userHasInteracted) { LatLng curLatlng = new LatLng(location.getLatitude(), location.getLongitude()); // ✅ 记录真实位置 myCurrentLat = location.getLatitude(); myCurrentLng = location.getLongitude(); isLocationReady = true; aMap.animateCamera(CameraUpdateFactory.newLatLngZoom(curLatlng, 16f)); userHasInteracted = true; // 获取城市 LatLonPoint point = new LatLonPoint(myCurrentLat, myCurrentLng); RegeocodeQuery query = new RegeocodeQuery(point, 200, GeocodeSearch.AMAP); try { geocodeSearch.getFromLocationAsyn(query); } catch (Exception e) { e.printStackTrace(); } aMap.setOnMyLocationChangeListener(null); } }; aMap.setOnMyLocationChangeListener(listener); } else { ActivityCompat.requestPermissions(requireActivity(), new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, LOCATION_PERMISSION_REQUEST_CODE); } } @Override public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) { if (requestCode == LOCATION_PERMISSION_REQUEST_CODE) { if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { if (aMap != null) { MyLocationStyle myLocationStyle = new MyLocationStyle(); myLocationStyle.myLocationType(MyLocationStyle.LOCATION_TYPE_LOCATION_ROTATE_NO_CENTER); aMap.setMyLocationStyle(myLocationStyle); aMap.setMyLocationEnabled(true); AMap.OnMyLocationChangeListener listener = location -> { if (location != null && !userHasInteracted) { LatLng curLatlng = new LatLng(location.getLatitude(), location.getLongitude()); // ✅ 同步记录位置 myCurrentLat = location.getLatitude(); myCurrentLng = location.getLongitude(); isLocationReady = true; aMap.animateCamera(CameraUpdateFactory.newLatLngZoom(curLatlng, 16f)); userHasInteracted = true; LatLonPoint point = new LatLonPoint(myCurrentLat, myCurrentLng); RegeocodeQuery query = new RegeocodeQuery(point, 200, GeocodeSearch.AMAP); try { geocodeSearch.getFromLocationAsyn(query); } catch (Exception e) { e.printStackTrace(); } aMap.setOnMyLocationChangeListener(null); } }; aMap.setOnMyLocationChangeListener(listener); } } else { Toast.makeText(requireContext(), "定位权限被拒绝，部分功能受限", Toast.LENGTH_LONG).show(); currentCity = "全国"; } } } @Override public void onRegeocodeSearched(RegeocodeResult result, int rCode) { if (rCode == 1000 && result != null && result.getRegeocodeAddress() != null) { String city = result.getRegeocodeAddress().getCity(); currentCity = (city != null && !city.isEmpty()) ? city : result.getRegeocodeAddress().getProvince(); } else { currentCity = "全国"; } } @Override public void onGeocodeSearched(com.amap.api.services.geocoder.GeocodeResult geocodeResult, int i) { // 忽略 } @Override public void onResume() { super.onResume(); mapView.onResume(); if (!userHasInteracted) { enableMyLocationLayer(); } } @Override public void onPause() { super.onPause(); mapView.onPause(); } @Override public void onDestroyView() { super.onDestroyView(); mapView.onDestroy(); inputTips = null; geocodeSearch = null; binding = null; } @Override public void onSaveInstanceState(@NonNull Bundle outState) { super.onSaveInstanceState(outState); mapView.onSaveInstanceState(outState); } // ✅ 完整保留原始的 setupSearchSuggestion 实现 private void setupSearchSuggestion() { try { inputTips = new Inputtips(requireContext(), new Inputtips.InputtipsListener() { @Override public void onGetInputtips(List<Tip> tipList, int rCode) { if (rCode == 1000 && tipList != null && !tipList.isEmpty()) { String[] arr = new String[tipList.size()]; for (int i = 0; i < tipList.size(); i++) { arr[i] = tipList.get(i).getName(); } ArrayAdapter<String> adapter = new ArrayAdapter<>( requireContext(), android.R.layout.simple_dropdown_item_1line, arr ); // ✅ 主线程执行 + 强制弹出 new Handler(Looper.getMainLooper()).post(() -> { // 不管哪个是焦点，都尝试设置两个输入框的 adapter binding.mapInput1.setAdapter(adapter); binding.mapInput2.setAdapter(adapter); // ✅ 关键修复：强制弹出下拉框 if (requireActivity().getCurrentFocus() == binding.mapInput1) { binding.mapInput1.showDropDown(); } else if (requireActivity().getCurrentFocus() == binding.mapInput2) { binding.mapInput2.showDropDown(); } }); } // ✅ 不再清空 adapter 或报错 —— 让用户保留上次有效建议 } }); } catch (Exception e) { e.printStackTrace(); Toast.makeText(requireContext(), "智能提示初始化失败", Toast.LENGTH_SHORT).show(); } Handler handler = new Handler(Looper.getMainLooper()); Runnable[] pending1 = {null}, pending2 = {null}; // 修改 mapInput1 监听器：移除延迟，改为直接请求 binding.mapInput1.addTextChangedListener(new TextWatcher() { @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) {} @Override public void onTextChanged(CharSequence s, int start, int before, int count) { // ✅ 清除上一个待执行任务 if (pending1[0] != null) { handler.removeCallbacks(pending1[0]); } // ✅ 输入为空则清空建议 if (s.length() == 0) { binding.mapInput1.setAdapter(null); return; } // ✅ 【核心】不再等 600ms，直接发起请求 try { inputTips.requestInputtips(s.toString(), currentCity); } catch (Exception e) { e.printStackTrace(); } } @Override public void afterTextChanged(Editable s) {} }); // 同样处理 mapInput2 binding.mapInput2.addTextChangedListener(new TextWatcher() { @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) {} @Override public void onTextChanged(CharSequence s, int start, int before, int count) { if (pending2[0] != null) { handler.removeCallbacks(pending2[0]); } if (s.length() == 0) { binding.mapInput2.setAdapter(null); return; } try { inputTips.requestInputtips(s.toString(), currentCity); } catch (Exception e) { e.printStackTrace(); } } @Override public void afterTextChanged(Editable s) {} }); // 回车事件保持不变 binding.mapInput1.setOnEditorActionListener((v, actionId, event) -> { if ((actionId & EditorInfo.IME_MASK_ACTION) == EditorInfo.IME_ACTION_SEARCH) { performSearch(); return true; } return false; }); binding.mapInput2.setOnEditorActionListener((v, actionId, event) -> { if ((actionId & EditorInfo.IME_MASK_ACTION) == EditorInfo.IME_ACTION_SEARCH) { performSearch(); return true; } return false; }); } private void handleSearchError(int rCode) { String msg; switch (rCode) { case 12: msg = "API Key 错误"; break; case 27: msg = "网络连接失败"; break; case 30: msg = "SHA1 或包名错误"; break; case 33: msg = "请求频繁"; break; default: msg = "搜索失败: " + rCode; break; } Toast.makeText(requireContext(), msg, Toast.LENGTH_SHORT).show(); } // ✅ 自定义 TextWatcher 类，保留原始写法 private static class SimpleTextWatcher implements android.text.TextWatcher { private final java.util.function.Consumer<CharSequence> onTextChanged; public SimpleTextWatcher(java.util.function.Consumer<CharSequence> onTextChanged) { this.onTextChanged = onTextChanged; } @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) {} @Override public void afterTextChanged(Editable s) {} @Override public void onTextChanged(CharSequence s, int start, int before, int count) { onTextChanged.accept(s); } } } HomeFragment代码如下：package com.example.bus.ui.home; import android.content.Intent; import android.os.Bundle; import android.os.Handler; import android.os.Looper; import android.text.Editable; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.view.inputmethod.EditorInfo; import android.widget.ArrayAdapter; import android.widget.Toast; import androidx.annotation.NonNull; import androidx.fragment.app.Fragment; import androidx.lifecycle.ViewModelProvider; import com.amap.api.services.help.Inputtips; import com.amap.api.services.help.Tip; import com.example.bus.MainActivity; import com.example.bus.SearchResultActivity; import com.example.bus.databinding.FragmentHomeBinding; import java.util.List; public class HomeFragment extends Fragment { private FragmentHomeBinding binding; private HomeViewModel homeViewModel; private Inputtips inputTips; private static final int TIPS_DELAY = 300; // 防抖延迟 private Handler handler = new Handler(Looper.getMainLooper()); private Runnable pendingRequest; @Override public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { binding = FragmentHomeBinding.inflate(inflater, container, false); View root = binding.getRoot(); // 初始化 ViewModel homeViewModel = new ViewModelProvider(this).get(HomeViewModel.class); homeViewModel.getText().observe(getViewLifecycleOwner(), text -> { binding.textHome.setText(text); }); setupSearchSuggestion(); setupSearchAction(); return root; } /** * 设置输入建议功能（suggestion） */ private void setupSearchSuggestion() { try { inputTips = new Inputtips(requireContext(), new Inputtips.InputtipsListener() { @Override public void onGetInputtips(List<Tip> tipList, int rCode) { if (rCode == 1000 && tipList != null && !tipList.isEmpty()) { String[] arr = new String[tipList.size()]; for (int i = 0; i < tipList.size(); i++) { arr[i] = tipList.get(i).getName(); } ArrayAdapter<String> adapter = new ArrayAdapter<>( requireContext(), android.R.layout.simple_dropdown_item_1line, arr ); // 主线程更新 UI 并弹出下拉 new Handler(Looper.getMainLooper()).post(() -> { binding.homeInput.setAdapter(adapter); binding.homeInput.showDropDown(); // ✅ 关键：强制弹出 }); } // 如果失败或无结果，不清空 adapter，保留上次有效建议 } }); } catch (Exception e) { e.printStackTrace(); Toast.makeText(requireContext(), "提示服务初始化失败", Toast.LENGTH_SHORT).show(); } // 添加文本监听 binding.homeInput.addTextChangedListener(new android.text.TextWatcher() { @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) { } @Override public void onTextChanged(CharSequence s, int start, int before, int count) { // 移除待执行请求（防抖） if (pendingRequest != null) { handler.removeCallbacks(pendingRequest); } if (s.length() == 0) { binding.homeInput.setAdapter(null); return; } pendingRequest = () -> { try { // 使用全国范围搜索 inputTips.requestInputtips(s.toString(), "全国"); } catch (Exception e) { e.printStackTrace(); } }; handler.postDelayed(pendingRequest, TIPS_DELAY); } @Override public void afterTextChanged(Editable s) { } }); } /** * 设置搜索动作：回车 & 按钮点击 */ private void setupSearchAction() { // 回车搜索 binding.homeInput.setOnEditorActionListener((v, actionId, event) -> { if ((actionId & EditorInfo.IME_MASK_ACTION) == EditorInfo.IME_ACTION_SEARCH) { performSearch(); return true; } return false; }); // 搜索按钮点击 binding.homeSearch.setOnClickListener(v -> performSearch()); } private void performSearch() { String keyword = binding.homeInput.getText().toString().trim(); if (keyword.isEmpty()) { Toast.makeText(requireContext(), "请输入关键词", Toast.LENGTH_SHORT).show(); return; } MainActivity activity = (MainActivity) requireActivity(); activity.ensureFineLocationPermission(() -> { Intent intent = new Intent(requireContext(), SearchResultActivity.class); intent.putExtra("keyword", keyword); startActivity(intent); }); } @Override public void onDestroyView() { super.onDestroyView(); binding = null; // 置空引用即可 inputTips = null; // 清理防抖任务 if (handler != null) { handler.removeCallbacksAndMessages(null); } } } SearchResultActivity代码如下：package com.example.bus; import android.Manifest; import android.content.Intent; import android.content.pm.PackageManager; import android.os.Bundle; import android.os.Handler; import android.os.Looper; import android.view.View; import android.widget.Button; import android.widget.TextView; import android.widget.Toast; import androidx.annotation.NonNull; import androidx.appcompat.app.AppCompatActivity; import androidx.core.app.ActivityCompat; import androidx.core.content.ContextCompat; import androidx.recyclerview.widget.LinearLayoutManager; import androidx.recyclerview.widget.RecyclerView; import com.amap.api.maps.AMap; import com.amap.api.maps.CameraUpdateFactory; import com.amap.api.maps.MapView; import com.amap.api.maps.UiSettings; import com.amap.api.maps.model.LatLng; import com.amap.api.maps.model.Marker; import com.amap.api.maps.model.MarkerOptions; import com.amap.api.maps.model.MyLocationStyle; import com.amap.api.services.core.LatLonPoint; import com.amap.api.services.core.PoiItem; import com.amap.api.services.poisearch.PoiResult; import com.amap.api.services.poisearch.PoiSearch; import com.amap.api.services.geocoder.GeocodeSearch; import com.amap.api.services.geocoder.RegeocodeQuery; import com.amap.api.services.geocoder.RegeocodeResult; import com.amap.api.services.help.Inputtips; import com.amap.api.services.help.Tip; import android.text.Editable; import android.text.TextWatcher; import android.widget.ArrayAdapter; import java.util.ArrayList; import java.util.List; import android.view.inputmethod.EditorInfo; public class SearchResultActivity extends AppCompatActivity implements PoiSearch.OnPoiSearchListener, GeocodeSearch.OnGeocodeSearchListener { private Button searchBtn, goToBtn; private RecyclerView resultListView; private List<PoiItem> poiList = new ArrayList<>(); private ResultAdapter adapter; private PoiSearch poiSearch; // 地图相关 private MapView mapView; private AMap aMap; private Marker selectedMarker; // 终点标记 // 输入提示 private Inputtips inputTips; private GeocodeSearch geocodeSearch; // 当前城市 private String currentCity = "全国"; // 是否已与地图交互（防止重复居中） private boolean userHasInteracted = false; private static final int LOCATION_PERMISSION_REQUEST_CODE = 1001; // 空状态提示视图 private TextView emptyView; // 【关键新增】保存定位得到的“我的位置” private double myCurrentLat = 0; private double myCurrentLng = 0; private boolean isLocationReady = false; // 定位是否完成 // 缓存从 HomeFragment 传来的关键词，等待定位完成后使用 private String pendingKeyword = null; // ✅ 新增：将搜索输入框提升为成员变量 private android.widget.AutoCompleteTextView searchInput; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_search_result); if (getSupportActionBar() != null) { getSupportActionBar().setDisplayHomeAsUpEnabled(true); getSupportActionBar().setTitle("搜索地点"); } initViews(); setupMap(savedInstanceState); setupSearchSuggestion(); try { geocodeSearch = new GeocodeSearch(this); geocodeSearch.setOnGeocodeSearchListener(this); } catch (Exception e) { e.printStackTrace(); } // ✅ 只缓存 keyword，不再尝试提前搜索 pendingKeyword = getIntent().getStringExtra("keyword"); // 删除以下三行：它们永远不会生效 // if (isLocationReady && pendingKeyword != null) { // runOnUiThread(() -> performSearchWithKeyword(pendingKeyword)); // } } private void initViews() { searchBtn = findViewById(R.id.search_btn); resultListView = findViewById(R.id.result_list); goToBtn = findViewById(R.id.btn_go_to); emptyView = findViewById(R.id.empty_view); searchInput = findViewById(R.id.search_input); // ✅ 初始化成员变量 goToBtn.setEnabled(false); adapter = new ResultAdapter(poiList, this::onPoiItemSelected); resultListView.setLayoutManager(new LinearLayoutManager(this)); resultListView.setAdapter(adapter); resultListView.setVisibility(View.GONE); emptyView.setVisibility(View.GONE); // 修改：传递真实定位点 goToBtn.setOnClickListener(v -> { if (selectedMarker == null) { Toast.makeText(this, "请先选择一个位置", Toast.LENGTH_SHORT).show(); return; } LatLng targetPos = selectedMarker.getPosition(); // 确保定位已完成 if (!isLocationReady) { Toast.makeText(this, "正在获取您的位置，请稍后再试", Toast.LENGTH_SHORT).show(); return; } Intent intent = new Intent(SearchResultActivity.this, RoutePlanActivity.class); intent.putExtra("start_lat", myCurrentLat); intent.putExtra("start_lng", myCurrentLng); intent.putExtra("target_lat", targetPos.latitude); intent.putExtra("target_lng", targetPos.longitude); intent.putExtra(RoutePlanActivity.EXTRA_SOURCE, RoutePlanActivity.SOURCE_FROM_SEARCH_RESULT); startActivity(intent); finish(); }); } private void setupMap(Bundle savedInstanceState) { mapView = findViewById(R.id.map_view); mapView.onCreate(savedInstanceState); aMap = mapView.getMap(); if (aMap != null) { initMapSettings(); } else { new Handler(Looper.getMainLooper()).post(() -> { aMap = mapView.getMap(); if (aMap != null) { initMapSettings(); } else { waitAMapReady(); } }); } } private void waitAMapReady() { new Handler(Looper.getMainLooper()).postDelayed(new Runnable() { int retry = 0; @Override public void run() { if (mapView == null) return; aMap = mapView.getMap(); if (aMap != null) { initMapSettings(); } else if (retry++ < 30) { new Handler(Looper.getMainLooper()).postDelayed(this, 100); } } }, 100); } private void initMapSettings() { UiSettings uiSettings = aMap.getUiSettings(); uiSettings.setZoomControlsEnabled(true); uiSettings.setCompassEnabled(true); uiSettings.setScrollGesturesEnabled(true); uiSettings.setMyLocationButtonEnabled(true); aMap.setOnMapClickListener(latLng -> { onCustomLocationSelected(latLng); }); // 初始视野：中国中心 new Handler(Looper.getMainLooper()).post(() -> aMap.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(35.8617, 104.1954), 4f)) ); enableMyLocationLayer(); } private void enableMyLocationLayer() { if (aMap == null) return; if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { MyLocationStyle myLocationStyle = new MyLocationStyle(); myLocationStyle.myLocationType(MyLocationStyle.LOCATION_TYPE_LOCATION_ROTATE_NO_CENTER); aMap.setMyLocationStyle(myLocationStyle); aMap.setMyLocationEnabled(true); AMap.OnMyLocationChangeListener listener = location -> { if (location != null && !userHasInteracted) { LatLng curLatlng = new LatLng(location.getLatitude(), location.getLongitude()); // 记录真实“我的位置” myCurrentLat = location.getLatitude(); myCurrentLng = location.getLongitude(); isLocationReady = true; // ✅ 先居中地图 aMap.animateCamera(CameraUpdateFactory.newLatLngZoom(curLatlng, 16f), 500, null); userHasInteracted = true; // 获取当前城市 LatLonPoint point = new LatLonPoint(myCurrentLat, myCurrentLng); RegeocodeQuery query = new RegeocodeQuery(point, 200, GeocodeSearch.AMAP); try { geocodeSearch.getFromLocationAsyn(query); } catch (Exception e) { e.printStackTrace(); } // ✅ 关键修改：延迟 800ms 再触发搜索，给地图留出渲染时间 new Handler(Looper.getMainLooper()).postDelayed(() -> { if (pendingKeyword != null && !pendingKeyword.isEmpty()) { performSearchWithKeyword(pendingKeyword); } }, 800); // 防止重复触发 aMap.setOnMyLocationChangeListener(null); } }; aMap.setOnMyLocationChangeListener(listener); } else { ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, LOCATION_PERMISSION_REQUEST_CODE); } } @Override public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) { super.onRequestPermissionsResult(requestCode, permissions, grantResults); if (requestCode == LOCATION_PERMISSION_REQUEST_CODE) { if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { enableMyLocationLayer(); } else { Toast.makeText(this, "定位权限被拒绝，部分功能受限", Toast.LENGTH_LONG).show(); currentCity = "全国"; } } } private void setupSearchSuggestion() { try { inputTips = new Inputtips(this, new Inputtips.InputtipsListener() { @Override public void onGetInputtips(List<Tip> tipList, int rCode) { if (rCode == 1000 && tipList != null && !tipList.isEmpty()) { String[] arr = new String[tipList.size()]; for (int i = 0; i < tipList.size(); i++) { arr[i] = tipList.get(i).getName(); } ArrayAdapter<String> adapter = new ArrayAdapter<>( SearchResultActivity.this, android.R.layout.simple_dropdown_item_1line, arr ); searchInput.setAdapter(adapter); searchInput.showDropDown(); } } }); } catch (Exception e) { e.printStackTrace(); } Handler handler = new Handler(Looper.getMainLooper()); Runnable[] pendingRunnable = {null}; searchInput.addTextChangedListener(new TextWatcher() { @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) {} @Override public void onTextChanged(CharSequence s, int start, int before, int count) { // ✅ 移除之前的延迟任务（防止堆积） if (pendingRunnable[0] != null) { handler.removeCallbacks(pendingRunnable[0]); } // ✅ 输入为空 → 清空下拉框 if (s.length() == 0) { searchInput.setAdapter(null); return; } // ✅ 【核心修改】不再等待，直接发起请求 try { inputTips.requestInputtips(s.toString(), currentCity); } catch (Exception e) { e.printStackTrace(); } } @Override public void afterTextChanged(Editable s) {} }); searchInput.setOnEditorActionListener((v, actionId, event) -> { if ((actionId & EditorInfo.IME_MASK_ACTION) == EditorInfo.IME_ACTION_SEARCH) { searchBtn.performClick(); return true; } return false; }); searchBtn.setOnClickListener(v -> { String keyword = searchInput.getText().toString().trim(); if (!keyword.isEmpty()) { performSearch(keyword); } else { Toast.makeText(this, "请输入关键词", Toast.LENGTH_SHORT).show(); } }); } // ✅ 修改：先设置文本，再模拟点击按钮（等价于用户操作） private void performSearchWithKeyword(String keyword) { searchInput.setText(keyword); searchInput.clearFocus(); searchBtn.performClick(); // ✅ 触发完整 UI 搜索流程 } private void performSearch(String keyword) { emptyView.setText("🔍 搜索中..."); emptyView.setVisibility(View.VISIBLE); resultListView.setVisibility(View.GONE); PoiSearch.Query query = new PoiSearch.Query(keyword, "", currentCity); query.setPageSize(20); query.setPageNum(0); if (isLocationReady) { LatLonPoint lp = new LatLonPoint(myCurrentLat, myCurrentLng); query.setLocation(lp); // 告诉高德“我在哪”，让它自行加权 } try { poiSearch = new PoiSearch(this, query); poiSearch.setOnPoiSearchListener(this); poiSearch.searchPOIAsyn(); } catch (Exception e) { Toast.makeText(this, "搜索失败", Toast.LENGTH_SHORT).show(); emptyView.setText("⚠️ 未找到相关地点"); } } private void onPoiItemSelected(PoiItem item) { LatLng latLng = new LatLng(item.getLatLonPoint().getLatitude(), item.getLatLonPoint().getLongitude()); if (selectedMarker != null) { selectedMarker.remove(); selectedMarker = null; } selectedMarker = aMap.addMarker(new MarkerOptions() .position(latLng) .title("终点：" + item.getTitle()) .icon(com.amap.api.maps.model.BitmapDescriptorFactory.defaultMarker( com.amap.api.maps.model.BitmapDescriptorFactory.HUE_RED))); aMap.animateCamera(CameraUpdateFactory.newLatLngZoom(latLng, 14f)); goToBtn.setEnabled(true); } private void onCustomLocationSelected(LatLng latLng) { if (selectedMarker != null) { selectedMarker.remove(); } selectedMarker = aMap.addMarker(new MarkerOptions() .position(latLng) .title("终点：自定义位置") .icon(com.amap.api.maps.model.BitmapDescriptorFactory.defaultMarker( com.amap.api.maps.model.BitmapDescriptorFactory.HUE_RED))); goToBtn.setEnabled(true); } @Override public void onPoiSearched(PoiResult result, int rCode) { if (rCode == 1000 && result != null && result.getPois() != null && !result.getPois().isEmpty()) { List<PoiItem> newPoiList = result.getPois(); poiList.clear(); poiList.addAll(newPoiList); adapter.notifyDataSetChanged(); resultListView.scrollToPosition(0); resultListView.setVisibility(View.VISIBLE); emptyView.setVisibility(View.GONE); // 先设置 Adapter 的选中状态 adapter.setSelected(0); // 再执行业务逻辑 onPoiItemSelected(poiList.get(0)); } else { emptyView.setText("⚠️ 未找到相关地点"); emptyView.setVisibility(View.VISIBLE); resultListView.setVisibility(View.GONE); } } @Override public void onPoiItemSearched(PoiItem item, int rCode) { // 必须实现 } @Override public void onRegeocodeSearched(RegeocodeResult result, int rCode) { if (rCode == 1000 && result != null && result.getRegeocodeAddress() != null) { String city = result.getRegeocodeAddress().getCity(); currentCity = (city != null && !city.isEmpty()) ? city : result.getRegeocodeAddress().getProvince(); } else { currentCity = "全国"; } } @Override public void onGeocodeSearched(com.amap.api.services.geocoder.GeocodeResult geocodeResult, int i) { // 忽略 } @Override protected void onResume() { super.onResume(); mapView.onResume(); } @Override protected void onPause() { super.onPause(); mapView.onPause(); } @Override protected void onDestroy() { super.onDestroy(); mapView.onDestroy(); inputTips = null; geocodeSearch = null; } @Override protected void onSaveInstanceState(@NonNull Bundle outState) { super.onSaveInstanceState(outState); mapView.onSaveInstanceState(outState); } @Override public boolean onSupportNavigateUp() { onBackPressed(); return true; } } 那我能否全都改用 PoiSearch 替代 InputTips，仅修改这个内容，最小量修改即可，代码中的其它内容保持原来不变。当然，能否尽量让POISearch弹出提示的速度更快一些？而且确保修改后的功能是不变的，在搜索过程中也是能够弹出提示，如果可以的话请你给我提供修改好的完整代码
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