android.widget.Switch – 开/关事件监听器？
我想实现一个开关按钮，android.widget.Switch（可从API v.14中获得）。
但我不知道如何添加一个事件监听器的按钮。 它应该是一个“onclick”的听众？ 我怎么知道它是否“打开”？
Switchinheritance了CompoundButton的属性，所以我会推荐OnCheckedChangeListener
mySwitch.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { // do something, the isChecked will be // true if the switch is in the On position } });
使用以下片段通过XML将切换添加到您的布局：
然后在您的Activity的onCreate方法中，获取对您的Switch的引用并设置其OnCheckedChangeListener：
Switch onOffSwitch = (Switch) findViewById(R.id.on_off_switch); onOffSwitch.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { Log.v("Switch State=", ""+isChecked); } });
定义你的XML布局：
然后创建一个活动
public class SwitchActivity extends ActionBarActivity implements CompoundButton.OnCheckedChangeListener { Switch mySwitch = null; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_switch); mySwitch = (Switch) findViewById(R.id.myswitch); mySwitch.setOnCheckedChangeListener(this); } @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { if (isChecked) { // do something when check is selected } else { //do something when unchecked } } **** }
========对于下面的API 14使用SwitchCompat =========
XML
活动
public class SwitchActivity extends ActionBarActivity implements CompoundButton.OnCheckedChangeListener { SwitchCompat mySwitch = null; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_switch); mySwitch = (SwitchCompat) findViewById(R.id.myswitch); mySwitch.setOnCheckedChangeListener(this); } @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { if (isChecked) { // do something when checked is selected } else { //do something when unchecked } } ***** }
Switch widget的布局是这样的。
在Activity类中，可以通过两种方式进行编码。 取决于你使用的代码。
第一条路
public class ActivityClass extends Activity implements CompoundButton.OnCheckedChangeListener { Switch list_toggle; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.return_vehicle); list_toggle=(Switch)findViewById(R.id.list_toggle); list_toggle.setOnCheckedChangeListener(this); } } public void onCheckedChanged(CompoundButton buttonView,boolean isChecked) { if(isChecked) { list_toggle.setText("Only Today's"); //To change the text near to switch Log.d("You are :", "Checked"); } else { list_toggle.setText("All List"); //To change the text near to switch Log.d("You are :", " Not Checked"); } }
第二种方式
public class ActivityClass extends Activity { Switch list_toggle; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.return_vehicle); list_toggle=(Switch)findViewById(R.id.list_toggle); list_toggle.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { if(isChecked) { list_toggle.setText("Only Today's"); //To change the text near to switch Log.d("You are :", "Checked"); } else { list_toggle.setText("All List"); //To change the text near to switch Log.d("You are :", " Not Checked"); } } }); } }
对于那些使用Kotlin的用户，可以为交换机设置一个监听器（在这种情况下，具有ID mySwitch ），如下所示：
mySwitch.setOnCheckedChangeListener { _, isChecked -> run { // do whatever you need to do when the switch is toggled here } }
如果当前选中开关（ON），则isChecked为true，否则为false。