Android 开发笔记___alertDialog

 public class AlertActivity extends AppCompatActivity implements OnClickListener {

     private TextView tv_alert;

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_alert);
         findViewById(R.id.btn_alert).setOnClickListener(this);
         tv_alert = (TextView) findViewById(R.id.tv_alert);
     }

     @Override
     public void onClick(View v) {
         if (v.getId() == R.id.btn_alert) {
             AlertDialog.Builder builder = new AlertDialog.Builder(this);
             builder.setTitle("尊敬的用户");
             builder.setMessage("你真的要卸载我吗？");
             builder.setPositiveButton("残忍卸载", new DialogInterface.OnClickListener() {
                 @Override
                 public void onClick(DialogInterface dialog, int which) {
                     tv_alert.setText("虽然依依不舍，还是只能离开了");
                 }
             });
             builder.setNegativeButton("我再想想", new DialogInterface.OnClickListener() {
                 @Override
                 public void onClick(DialogInterface dialog, int which) {
                     tv_alert.setText("让我再陪你三百六十五个日夜");
                 }
             });
             AlertDialog alert = builder.create();
             alert.show();
         }
     }

 }