Question

我有这个ImageView，它显示来自URL的图片。我希望有一个按钮，单击该按钮将显示URL中的图像。谁能教我怎么做？

这是我的代码：

＆＃13;

 String url = "https://www.google.com.ph/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&ved=0ahUKEwiGzJm-l5PWAhVJl5QKHegTAg0QjBwIBA&url=https%3A%2F%2Fwww.enterprise.co.uk%2Fcontent%2Fdam%2Fglobal-vehicle-images%2Fcars%2FVAUX_INSI_2014.png&psig=AFQjCNGerQpF4NHcx50OFhQ2AGUlJYQCpQ&ust=1504877444951754";
    ImageView imageView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);

        setContentView(R.layout.activity_main);

        imageView = (ImageView)findViewById(R.id.imageView);
        loadImageFromUrl(url);
    }

    private void loadImageFromUrl(String url) {
        Picasso.with(this) .load(url) .placeholder(R.mipmap.ic_launcher)
                .error(R.mipmap.ic_launcher)
                .into(imageView, new com.squareup.picasso.Callback() {

                    @Override
                    public void onSuccess() {

                    }

                    @Override
                    public void onError() {

                    }
                });
    }

＆＃13;

毕加索：

＆＃13;

compile 'com.squareup.picasso:picasso:2.5.2'

＆＃13;

Answer 1

点击视图时调用。

MyPassword

Answer 2

在xml文件中添加一个按钮。让它与id：btn_load;

在活动内添加

Button btn = findViewById(R.id.btn_load);
btn.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        loadImageFromUrl(url);
    }
});

Answer 3

在xml布局文件中创建一个按钮。然后在onCreate调用：

final String url = "https://www.google.com.ph/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&ved=0ahUKEwiGzJm-l5PWAhVJl5QKHegTAg0QjBwIBA&url=https%3A%2F%2Fwww.enterprise.co.uk%2Fcontent%2Fdam%2Fglobal-vehicle-images%2Fcars%2FVAUX_INSI_2014.png&psig=AFQjCNGerQpF4NHcx50OFhQ2AGUlJYQCpQ&ust=1504877444951754";
ImageView imageView;
Button button;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    this.requestWindowFeature(Window.FEATURE_NO_TITLE);
    this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
            WindowManager.LayoutParams.FLAG_FULLSCREEN);

    setContentView(R.layout.activity_main);

    imageView = (ImageView)findViewById(R.id.imageView);

    button = findViewById(R.id.button_id);
    button.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            loadImageFromUrl(url);    
        }
    });
}

注意：要使其工作，您必须将您的url String声明为 final ，因为您在匿名类（OnClickListener）中使用它。

注意2：您拥有的图片网址可能无效。请改用此https://www.enterprise.co.uk/content/dam/global-vehicle-images/cars/VAUX_INSI_2014.png

在按钮单击时从URL加载图像

3 个答案: