自定义对话框单击监听器android?
我创建了一个扩展dialog类的自定义对话框自定义对话框单击监听器android?,android,interface,dialog,Android,Interface,Dialog,我创建了一个扩展dialog类的自定义对话框 public class CustomAlertDialog extends Dialog implements View.OnClickListener { private TextView tvAlertTitle, tvAlertMessage; private Button butAlertOk, butAlertCancel; private CustomAlertDialog.OnButtonClick onButtonClick;
public class CustomAlertDialog extends Dialog implements View.OnClickListener {
private TextView tvAlertTitle, tvAlertMessage;
private Button butAlertOk, butAlertCancel;
private CustomAlertDialog.OnButtonClick onButtonClick;
public CustomAlertDialog(Context context) {
super(context);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
this.setContentView(R.layout.layout_alert_dialog);
initViews();
}
//initialise views
private void initViews() {
tvAlertTitle = (TextView) findViewById(R.id.textViewAlertTitle);
tvAlertMessage = (TextView) findViewById(R.id.textViewAlertMessage);
butAlertOk = (Button) findViewById(R.id.buttonAlertOk);
butAlertCancel = (Button) findViewById(R.id.buttonAlertCancel);
butAlertOk.setOnClickListener(this);
butAlertCancel.setOnClickListener(this);
}
//set title for dialog
public void setAlertTitle(String title) {
tvAlertTitle.setText(title);
}
//set message for dialog
public void setAlertMessage(String message) {
tvAlertMessage.setText(message);
}
@Override
public void onClick(View v) {
if (v == butAlertOk) {
onButtonClick.onOkButtonClick();
}
if (v == butAlertCancel) {
onButtonClick.onCancelButtonClick();
}
}
public interface OnButtonClick {
void onOkButtonClick();
void onCancelButtonClick();
}
}
这是我的XML
<?xml version="1.0" encoding="utf-8"?>
}
当我点击任何一个按钮时,我得到这个异常
java.lang.NullPointerException
at com.vfirst.ui.CustomAlertDialog.onClick(CustomAlertDialog.java:57)
at android.view.View.performClick(View.java:4575)
at android.view.View$PerformClick.run(View.java:18578)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5127)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:825)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:641)
at dalvik.system.NativeStart.main(Native Method)
代码有什么问题?我是否正确实现了该接口?您没有初始化
onbutton单击
接口,因此当您尝试访问该接口时,该接口为空,从而导致NullPointerException
。您可以这样做
public CustomAlertDialog(Context context) {
super(context);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
this.setContentView(R.layout.layout_alert_dialog);
initViews();
if (context instanceof CustomAlertDialog.OnButtonClick) {
onButtonClick = (CustomAlertDialog.OnButtonClick)context;
}
}
错误是因为您尚未初始化
on按钮单击CustomAlertDialog
类中的。在CustomAlertDialog
中添加此方法
public void setListener(CustomAlertDialog.OnButtonClic onButtonClick){
this.onButtonClick = onButtonClick;
}
从创建此对话框的片段中调用此方法
customAlertDialog.setListener(this);
并检查onButtonClick
在onClick
public void onClick(View v) {
if(onButtonClick !=null){
if (v == butAlertOk) {
onButtonClick.onOkButtonClick();
}
if (v == butAlertCancel) {
onButtonClick.onCancelButtonClick();
}
}
}
您忘记初始化onButtonClick。谢谢,这只是问题所在。现在,当我在片段中使用它时,我发现这个错误HomeActivity不能转换为CustomAlertDialog$OnButtonClickI,我将它初始化为CustomAlertDialog=new CustomAlertDialog(getActivity()),谢谢,这只是个问题。现在,当我在片段中使用它时,我收到以下错误:HomeActivity不能强制转换到CustomAlertDialog$OnButton单击…我将其初始化为CustomAlertDialog=new CustomAlertDialog(getActivity())@WISHY更新了我的答案,请查看
customAlertDialog.setListener(this);
public void onClick(View v) {
if(onButtonClick !=null){
if (v == butAlertOk) {
onButtonClick.onOkButtonClick();
}
if (v == butAlertCancel) {
onButtonClick.onCancelButtonClick();
}
}
}