13.事件处理和手势

基于监听的事件处理

略

基于回调的事件处理

package com.example.demo;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        Toast.makeText(MainActivity.this,"触摸",Toast.LENGTH_SHORT).show();
        return super.onTouchEvent(event);
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        Toast.makeText(MainActivity.this,"向下",Toast.LENGTH_SHORT).show();
        return super.onKeyDown(keyCode, event);
    }

    @Override
    public boolean onKeyUp(int keyCode, KeyEvent event) {
        Toast.makeText(MainActivity.this,"抬起",Toast.LENGTH_SHORT).show();
        return super.onKeyUp(keyCode, event);
    }
}