我在Mainactivity.java中写了一个openDialog()用来做事件响应.但在按钮OnClick属性中加入openDialog()没效果,提示openDialog()找不到public class MainActivity extends Activity {
private TextView txtView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
this.txtView = (TextView) findViewById(R.id.textView1); if(this.txtView!=null){ this.txtView.setText("Hello World");
}
}
public void openDialog(){
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Hello");
builder.setMessage("Hello World \n");
builder.setNegativeButton("OK",null);
builder.show();
} @Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
添加Button的On Click属性eclipseadtjava
private TextView txtView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
this.txtView = (TextView) findViewById(R.id.textView1); if(this.txtView!=null){ this.txtView.setText("Hello World");
}
}
public void openDialog(){
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Hello");
builder.setMessage("Hello World \n");
builder.setNegativeButton("OK",null);
builder.show();
} @Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
添加Button的On Click属性eclipseadtjava
public class MainActivity extends Activity {
private TextView txtView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
this.txtView = (TextView) findViewById(R.id.textView1);
if(this.txtView!=null){
this.txtView.setText("Hello World");
} Button button = (Button) findViewById(R.id.button_id);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
openDialog();
}
});
}
public void openDialog(){
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Hello");
builder.setMessage("Hello World \n");
builder.setNegativeButton("OK",null);
builder.show();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
public void openDialog(View view) {
// ...
}
方法要定义成public,并且接受一个View做参数,你这里少了这个参数是不行的。
或者用2楼的方法,用代码实现。