Android volume key monitoring and android Volume monitoring

Android volume key monitoring and android Volume monitoring

Conclusion:

The following two methods can be used to obtain the volume key. During the test, we found that

When KeyEvent. KEYCODE_VOLUME_UP is held down all the time, Samsung's tablet counts to 200, and this event is not triggered;

Therefore, when KeyEvent. ACTION_DOWN is changed, a method is started to count the number of stop techniques of KeyEvent. ACTION_UP;

package com.akm.testvolume; import android.app.Activity;import android.os.Bundle;import android.view.KeyEvent;import android.widget.TextView; public class MainActivity extends Activity {    private TextView tv;     @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        tv = (TextView) findViewById(R.id.tv);    }     int count = -1;     @Override    public boolean dispatchKeyEvent(KeyEvent event) {         int action = event.getAction();         if (action ==KeyEvent.ACTION_DOWN) {            tv.setText("+++++++++ACTION_DOWN++++++"+ count++);            return true;        }         if (action== KeyEvent.ACTION_UP) {            tv.setText("+++++ACTION_UP++++++++++");            return true;        }         return super.dispatchKeyEvent(event);    }       @Override    public boolean onKeyDown(int keyCode, KeyEvent event) {        switch (keyCode) {         case KeyEvent.KEYCODE_VOLUME_DOWN:             tv.setText("-----------------"+count);            count--;             return true;         case KeyEvent.KEYCODE_VOLUME_UP:            tv.setText("++++++++++++++++"+ count);            count++;            return true;        case KeyEvent.KEYCODE_VOLUME_MUTE:            tv.setText("MUTE");             return true;        }        return super.onKeyDown(keyCode, event);    } }