布局
<LinearLayout
android:orientation="vertical"
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<TextView
android:id="@+id/te"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_gravity="center"
android:gravity="center"
android:background="#00f"
android:textSize="25sp"
android:text="5"
android:layout_marginTop="150dp"
/>
</LinearLayout>
主代码
package com.ang.l;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
public class MainActivity extends BaseActivity {
private TextView te;
private SharedPreferences sp;
@Override
public int bindLayout() {
return R.layout.activity_main;
}
@Override
public void initView() {
te = findViewById(R.id.te);
//获取sp 第一个是文件名 第二个参数是文件访问权限
sp = getSharedPreferences("login", Context.MODE_PRIVATE);
}
@Override
public void initData() {
//判断是否自动登录
if(sp.getBoolean("自动登录",false)){
startActivity(new Intent(MainActivity.this,SecondActivity.class));
finish();
//移除
handler.removeCallbacksAndMessages(null);
return ;
}
}
@Override
public void bindEvent() {
te.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
SharedPreferences.Editor edit = sp.edit();
edit.putBoolean("自动登录",true);
edit.commit();
startActivity(new Intent(MainActivity.this,SecondActivity.class));
finish();
//移除
handler.removeCallbacksAndMessages(null);
}
});
//发送消息
handler.sendEmptyMessageDelayed(0,1000);
}
//销毁
@Override
protected void onDestroy() {
super.onDestroy();
//移除
handler.removeCallbacksAndMessages(null);
}
int time=5;
Handler handler=new Handler(){
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
switch (msg.what){
case 0:
time--;
if(time>0){
te.setText(time+"");
handler.sendEmptyMessageDelayed(0,1000);
}else{
SharedPreferences.Editor edit = sp.edit();
edit.putBoolean("自动登录",true);
edit.commit();
startActivity(new Intent(MainActivity.this,SecondActivity.class));
finish();
}
break;
}
}
};
}
注意:清单文件里面注册一下
<activity android:name=".SecondActivity"/>