Android - Imageview和setOnClickListener

Question

请解释我为什么代码不起作用。谢谢你的帮助。

private boolean emotico = false;

ImageView emot = (ImageView) findViewById(R.id.obrazek);
emot.setClickable(true);
emot.setOnClickListener(new View.OnClickListener() {

    public void onClick(View v){
    ImageView emotico = (ImageView) findViewById(R.id.obrazek);
    if (emot) {
        emotico.setImageResource(R.drawable.ic2);
    } else {
        emotico.setImageResource(R.drawable.ic1);
    }
    emot = !emot;
}
}

Answer 1

此代码适用于您：

//emotico is a boolean variable
private boolean emotico = false;

//emot is a ImageView variable
ImageView emot = (ImageView) findViewById(R.id.obrazek);
emot.setClickable(true);
emot.setOnClickListener(new View.OnClickListener() {

    public void onClick(View v){
    //Two errors in your below line:
    //1. 'emotico' is a boolean and 'emot' being a ImageView variable can't be used together
    //2. You have already defined and instantiated it above, so no need to do it again
    //ImageView emotico = (ImageView) findViewById(R.id.obrazek);

    //we check for boolean conditions
    if (emotico) {
        //ImageView variable should be assigned here
        emot.setImageResource(R.drawable.ic2);
    } else {
        //ImageView variable should be assigned here
        emot.setImageResource(R.drawable.ic1);
    }
    //check for boolean condition here
    emotico = !emotico;
  }
}

Answer 2

你正在混淆的东西，你正试图再次映射imageview的onClickListener（），请试试这个！

private boolean emotico = false;

ImageView emot = (ImageView) findViewById(R.id.obrazek);
emot.setClickable(true);
emot.setOnClickListener(new View.OnClickListener() {

    public void onClick(View v){

    if (emotico) {
        emot.setImageResource(R.drawable.ic2);
    } else {
        emot.setImageResource(R.drawable.ic1);
    }
    emotico = !emotico ;
}
}

试试这个代码！希望它能解决你的问题！ ：）

Answer 3

我认为您在emot(ImageView)

中将emotico(boolean flag)与onClick()混为一谈

private boolean emotico = false;

final ImageView emot = (ImageView) findViewById(R.id.obrazek);
emot.setClickable(true);
emot.setOnClickListener(new View.OnClickListener() {
   public void onClick(View v){
     emotico = !emotico;
     if (emotico) {
        emot.setImageResource(R.drawable.ic2);
     } else {
        emot.setImageResource(R.drawable.ic1);
     }
   }
}