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技術社區[雲棲]
自定義控件讓TextView、Button的drawableLeft和drawableRight與文本一起居中顯示
TextView的drawableLeft、drawableRight和drawableTop是一個常用、好用的屬性，可以在文本的上下左右放置一個圖片，而不使用更加複雜布局就能達到，我也常常喜歡用RadioButton的這幾個屬性實現很多效果，但是苦於不支持讓drawbleLeft與文本一起居中，設置gravity為center也無濟於事，終於有空研究了一下，這裏與大家一起分享。
布局XML
<com.assistant.expand.customview.DrawableCenterButton
android:gravity="left|center_vertical"
android:drawableLeft="@drawable/icon_erweima"
android:drawablePadding="5dp"
android:
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@android:color/transparent"
android:singleLine="true"
android:text="掃描二維碼簽到"
android:textColor="@color/color_button2"
android:textSize="17sp" />
/**
* drawableLeft與文本一起居中顯示
*
*
*/
public class DrawableCenterTextView extends TextView {
public DrawableCenterTextView(Context context, AttributeSet attrs,
int defStyle) {
super(context, attrs, defStyle);
}
public DrawableCenterTextView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public DrawableCenterTextView(Context context) {
super(context);
}
@Override
protected void onDraw(Canvas canvas) {
Drawable[] drawables = getCompoundDrawables();
if (drawables != null) {
Drawable drawableLeft = drawables[0];
if (drawableLeft != null) {
float textWidth = getPaint().measureText(getText().toString());
int drawablePadding = getCompoundDrawablePadding();
int drawableWidth = 0;
drawableWidth = drawableLeft.getIntrinsicWidth();
float bodyWidth = textWidth + drawableWidth + drawablePadding;
canvas.translate((getWidth() - bodyWidth) / 2, 0);
}
}
super.onDraw(canvas);
}
}
下麵是用Button的Right 例子
/**
* drawableRight與文本一起居中顯示
*
*
*/
public class DrawableCenterButton extends Button {
public DrawableCenterButton(Context context) {
super(context);
// TODO Auto-generated constructor stub
}
public DrawableCenterButton(Context context, AttributeSet attrs,
int defStyle) {
super(context, attrs, defStyle);
}
public DrawableCenterButton(Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
protected void onDraw(Canvas canvas) {
Drawable[] drawables = getCompoundDrawables();
if (drawables != null) {
Drawable drawableLeft = drawables[2];
if (drawableLeft != null) {
float textWidth = getPaint().measureText(getText().toString());
int drawablePadding = getCompoundDrawablePadding();
int drawableWidth = 0;
drawableWidth = drawableLeft.getIntrinsicWidth();
float bodyWidth = textWidth + drawableWidth + drawablePadding;
setPadding(0, 0, (int)(getWidth() - bodyWidth), 0);
canvas.translate((getWidth() - bodyWidth) / 2, 0);
}
}
super.onDraw(canvas);
}
}
最後更新：2017-04-03 12:56:20