ZXing+LeakCanary使用
一.生成二维码和扫描二维码
1.依赖:
implementation 'cn.yipianfengye.android:zxing-library:2.2'
2.权限:
<!--网络权限-->
<uses-permission android:name="android.permission.INTERNET"/>
<!--震动权限-->
<uses-permission android:name="android.permission.VIBRATE"/>
<!--摄像头权限-->
<uses-permission android:name="android.permission.CAMERA"/>
<!--自动聚焦权限-->
<uses-feature android:name="android.hardware.camera.autofocus"/>
3.动态权限:
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
requestPermissions(new String[]{Manifest.permission.CAMERA,Manifest.permission.VIBRATE,Manifest.permission.WRITE_EXTERNAL_STORAGE}, 200);
}
4.application初始化ZXing:
创建一个App
public class App extends Application {
@Override
public void onCreate() {
super.onCreate();
//初始化Zxing库
ZXingLibrary.initDisplayOpinion(this);
}
}
5.清单文件:
记得在清单文件中去声明App
android:name=".App"
6.生成二维码:
bt.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.mipmap.ic_launcher);
Bitmap code = CodeUtils.createImage("你好呀", 400, 400, bitmap);
iv.setImageBitmap(code);
}
});
7.扫描二维码:
bt1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, CaptureActivity.class);
startActivityForResult(intent,101);
}
});
@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == 101 && resultCode == Activity.RESULT_OK){
Bundle extras = data.getExtras();
if (extras != null){
String string = extras.getString(CodeUtils.RESULT_STRING);
Toast.makeText(this, "扫描结果"+string, Toast.LENGTH_SHORT).show();
}
}
}
8.所有代码:
import android.Manifest;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Build;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import com.uuzuche.lib_zxing.activity.CaptureActivity;
import com.uuzuche.lib_zxing.activity.CodeUtils;
public class MainActivity extends AppCompatActivity {
private Button bt;
private ImageView iv;
private Button bt1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
requestPermissions(new String[]{Manifest.permission.CAMERA, Manifest.permission.VIBRATE, Manifest.permission.WRITE_EXTERNAL_STORAGE}, 200);
}
initView();
bt.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.mipmap.ic_launcher);
Bitmap code = CodeUtils.createImage("你好呀", 400, 400, bitmap);
iv.setImageBitmap(code);
}
});
bt1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, CaptureActivity.class);
startActivityForResult(intent,101);
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == 101 && resultCode == Activity.RESULT_OK){
Bundle extras = data.getExtras();
if (extras != null){
String string = extras.getString(CodeUtils.RESULT_STRING);
Toast.makeText(this, "扫描结果"+string, Toast.LENGTH_SHORT).show();
}
}
}
private void initView() {
bt = (Button) findViewById(R.id.bt);
iv = (ImageView) findViewById(R.id.iv);
bt1 = (Button) findViewById(R.id.bt1);
}
}
二.LeakCanary内存泄漏
1.什么是LeakCanary
LeakCanary是大名鼎鼎的square公司开源的内存泄漏检测工具,目前上大部分app在开发测试阶段都会接入此工具用于检测潜在的内存泄漏问题。
2.依赖:
//导入LeakCanary的依赖,去定位页面的内存泄漏问题。
debugImplementation 'com.squareup.leakcanary:leakcanary-android:1.6.3'
releaseImplementation 'com.squareup.leakcanary:leakcanary-android-no-op:1.6.3'
debugImplementation 'com.squareup.leakcanary:leakcanary-support-fragment:1.6.3'
3.application中部署:
在App里面,如上
//部署leakcanary,定位内存泄漏
if(!LeakCanary.isInAnalyzerProcess(this)){//如果没有部署
LeakCanary.install(this);//部署
}
4.制造内存泄漏现象:
/***
单例模式的TestManager
*/
public class TestManager {
private List<Activity> list = new ArrayList<>();
private static TestManager testManager;
public static TestManager getInstance(){
if(testManager == null){
testManager = new TestManager();
}
return testManager;
}
public void add(Activity activity){
list.add(activity);
}
}
然后创建两个LeakActivity
public class LeakActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_leak);
findViewById(R.id.bt).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(LeakActivity.this,Leak2Activity.class);
startActivity(intent);
}
});
}
}
public class Leak2Activity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_leak2);
TestManager.getInstance().add(this);
}
}
跳转以后会出现一个Leaks的图标
点击进去可以查看内存泄漏原因