如何在警报对话框中的每个项目之前添加图标？

Question

我正在使用AlertDialog（请参见下面的代码），并希望在每个文本之前放置一个图像。

例如，电子邮件图标，然后输入文本“ Email”，Facebook图标，然后输入文本“ Facebook”，等等。

使用以下代码，如何在每个文本值之前添加图标？

final CharSequence[] items = { "Email", "Facebook", "Twitter", "LinkedIn" };
AlertDialog.Builder builder = new AlertDialog.Builder(More.this);
builder.setTitle("Share Appliction");
builder.setItems(items, new DialogInterface.OnClickListener() {
    @Override
    public void onClick(DialogInterface dialog, int item) {
        if (item == 0) {

        } else if (item == 1) {

        } else if (item == 2) {

        } else if(item == 3) {

        }
    }
});
AlertDialog alert = builder.create();
alert.show();

Answer 1

您需要自定义ListAdapter来添加图像。 一种方法是将ArrayAdapter子类化（默认由AlertDialog ）。 这是一个例子：

final Item[] items = {
    new Item("Email", android.R.drawable.ic_menu_add),
    new Item("Facebook", android.R.drawable.ic_menu_delete),
    new Item("...", 0),//no icon for this one
};

ListAdapter adapter = new ArrayAdapter<Item>(
    this,
    android.R.layout.select_dialog_item,
    android.R.id.text1,
    items){
        public View getView(int position, View convertView, ViewGroup parent) {
            //Use super class to create the View
            View v = super.getView(position, convertView, parent);
            TextView tv = (TextView)v.findViewById(android.R.id.text1);

            //Put the image on the TextView
            tv.setCompoundDrawablesWithIntrinsicBounds(items[position].icon, 0, 0, 0);

            //Add margin between image and text (support various screen densities)
            int dp5 = (int) (5 * getResources().getDisplayMetrics().density + 0.5f);
            tv.setCompoundDrawablePadding(dp5);

            return v;
        }
    };


new AlertDialog.Builder(this)
    .setTitle("Share Appliction")
    .setAdapter(adapter, new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int item) {
            //...
        }
    }).show();

这是Item类

public static class Item{
    public final String text;
    public final int icon;
    public Item(String text, Integer icon) {
        this.text = text;
        this.icon = icon;
    }
    @Override
    public String toString() {
        return text;
    }
}

Answer 2

做这样的事情：

ViewGroup layout=new LinearLayout(context);
TextView tv=new TextView(context); //your text
tv.setText("my text"); 
ImageView imageView=new ImageView(context); //your icon
//filling image view with icon bitmap (in this case from resource)
imageView.setImageBitmap(BitmapFactory.decodeStream(context.getResources().openRawResource(resourceId)));
//ensuring that icon size will be more or less like text height
imageView.setAdjustViewBounds(true);
imageView.setMaxHeight((int )(tv.getLineHeight()*1.5));
imageView.setScaleType(ImageView.ScaleType.CENTER_INSIDE);
layout.addView(imageView); //adding icon
tv.setGravity(Gravity.BOTTOM|Gravity.LEFT);
layout.addView(tv); //adding text

总的想法是创建布局/视图组并将图标+文本+所需的任何内容添加到视图组

Answer 3

要缩放图像：

//Put the image on the TextView
int dp50 = (int) (50 * getResources().getDisplayMetrics().density + 0.5f);
Drawable dr = getResources().getDrawable(R...YOUR_DRAWABLE);
Bitmap bitmap = ((BitmapDrawable) dr).getBitmap();
Drawable d = new BitmapDrawable(getResources(), Bitmap.createScaledBitmap(bitmap, dp50, dp50, true));
tv.setCompoundDrawablesWithIntrinsicBounds(d, null, null, null);

// Add margin between image and text (support various screen densities)
int dp10 = (int) (10 * getResources().getDisplayMetrics().density + 0.5f);
tv.setCompoundDrawablePadding(dp10);

Answer 4

我喜欢Tom Esterez的解决方案，但建议使用相对函数代替RTL支持。

所以使用这个：

tv.setCompoundDrawablesRelativeWithIntrinsicBounds(items[position].iconID, 0, 0, 0);

代替这个：

tv.setCompoundDrawablesWithIntrinsicBounds(items[position].iconID, 0, 0, 0);