利用dialog.getButton().setEnabled()实现按钮使能

	<span style="font-family: Arial, Helvetica, sans-serif;">   AlertDialog.Builder builder = new AlertDialog.Builder(CheckTableActivity.this);</span>
LayoutInflater inflater = getLayoutInflater();
View view = inflater.inflate(R.layout.input_dialog, null);
dg_danger = (EditText) view.findViewById(R.id.editText1);
dg_score = (EditText) view.findViewById(R.id.editText2);
dg_spinner = (Spinner) view.findViewById(R.id.spinner1);

final int num = vp_curr>0?(vp_curr-1):0;
danger_flag = 0;
score_flag = 0;

// Inflate and set the layout for the dialog
// Pass null as the parent view because its going in the dialog layout
builder.setView(view)
// Add action buttons
.setPositiveButton("确认",
new DialogInterface.OnClickListener()
{
@Override
public void onClick(DialogInterface dialog, int id)
{
addListItem(num, dg_danger.getText().toString(), dg_score.getText().toString());
System.out.println(dg_danger.getText().toString() + ";" + dg_score.getText().toString());
}
}).setNegativeButton("取消", null).setTitle("添加隐患条目");
AlertDialog ad = builder.create();
ad.setView(view);
ad.show();
//show之后再获取按钮

final Button positiveButton = ad.getButton(AlertDialog.BUTTON_POSITIVE);

positiveButton.setEnabled(false);
System.out.println("setEnabled false");

//edittext文本改变监听，下同
dg_danger.addTextChangedListener(new TextWatcher()
{
@Override
public void afterTextChanged(Editable arg0) {
System.out.println("danger changed");
if(arg0.toString().trim().equals("")){
danger_flag = 0;
positiveButton.setEnabled(false);
System.out.println("set enabled false");
} else {
danger_flag = 1;
if(score_flag == 1)
{
positiveButton.setEnabled(true);
System.out.println("set enabled true");
}
}
}
public void beforeTextChanged(CharSequence arg0, int arg1, int arg2, int arg3) { }
public void onTextChanged(CharSequence arg0, int arg1, int arg2, int arg3) {}
});
dg_score.addTextChangedListener(new TextWatcher()
{
@Override
public void afterTextChanged(Editable arg0) {
System.out.println("score changed");
if(arg0.toString().equals("")){
score_flag = 0;
positiveButton.setEnabled(false);
System.out.println("set enabled false");
} else {
score_flag = 1;
if(danger_flag == 1)
{
positiveButton.setEnabled(true);
System.out.println("set enabled true");
}
}
}
public void beforeTextChanged(CharSequence arg0, int arg1, int arg2, int arg3) { }
public void onTextChanged(CharSequence arg0, int arg1, int arg2, int arg3) {}
}
);