Gallery中内容居左的方法 ——重写Gallery

开发时遇到一个界面美观问题：

Gallery 中的内容默认居中，想让其居左，找了很多资料都不太理想，最后终于找到一个重写Gallery 的办法，试验后发现是好用的~。

 

以下即为重写的 MyGallery 代码。

 

再在布局中把

 <Gallery

  ...

 />

 

换成使用自定义的 MyGallery 即可

 <包名.MyGallery

  ...

 />

 

Gallery 元素左对齐的方法 重写Gallery

 

转载自http://www.eoeandroid.com/thread-158088-1-1.html

 

方法是重写Gallery，但让Gallery居中的那个方法是私有的，无法重写，用下面重写的Gallery就可以。

 

import android.R.attr;

import android.content.Context;

import android.content.res.TypedArray;

import android.graphics.Camera;

import android.graphics.Matrix;

import android.util.AttributeSet;

import android.view.MotionEvent;

import android.view.View;

import android.view.animation.Transformation;

import android.widget.Gallery;

 

public class MyGallery extends Gallery {

        private Camera mCamera;

        private int mWidth;

        private int mPaddingLeft;

        private boolean flag;

        private static int firstChildWidth;

        private static int firstChildPaddingLeft;

 

       

        public MyGallery(Context context) {

                super(context);

                mCamera = new Camera();

                this.setStaticTransformationsEnabled(true);

        }

 

       

        public MyGallery(Context context, AttributeSet attrs) {

                super(context, attrs);

                mCamera = new Camera();

                //setAttributesValue(context, attrs);

                this.setStaticTransformationsEnabled(true);

        }

 

       

        public MyGallery(Context context, AttributeSet attrs, int defStyle) {

                super(context, attrs, defStyle);

                mCamera = new Camera();

                //setAttributesValue(context, attrs);

                this.setStaticTransformationsEnabled(true);

        }

 

        private void setAttributesValue(Context context, AttributeSet attrs) {

                TypedArray typedArray = context.obtainStyledAttributes(attrs, new int[] { attr.paddingLeft });

                mPaddingLeft = typedArray.getDimensionPixelSize(0, 0);

                typedArray.recycle();

        }

 

        protected boolean getChildStaticTransformation(View child, Transformation t) {

                t.clear();

                t.setTransformationType(Transformation.TYPE_MATRIX);

                mCamera.save();

                final Matrix imageMatrix = t.getMatrix();

                final int imageHeight = child.getLayoutParams().height;

                final int imageWidth = child.getLayoutParams().width;

                if (flag) {

                        firstChildWidth = getChildAt(0).getWidth();

                        firstChildPaddingLeft = getChildAt(0).getPaddingLeft();

                        flag = false;

                }

                mCamera.translate(firstChildWidth / 2 + firstChildPaddingLeft + mPaddingLeft - mWidth / 2, 0f, 0f);

                mCamera.getMatrix(imageMatrix);

                mCamera.restore();

                return true;

        }

 

        protected void onSizeChanged(int w, int h, int oldw, int oldh) {

                if (!flag) {

                        mWidth = w ;

                        getLayoutParams().width = mWidth;

                        flag = true;

                }

                super.onSizeChanged(w, h, oldw, oldh);

        }

 

        @Override

        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {

                // TODO Auto-generated method stub

                // return super.onFling(e1, e2, velocityX, velocityY);

                return false;

        }

 

        @Override

        public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {

                // TODO Auto-generated method stub

                return super.onScroll(e1, e2, distanceX, distanceY);

        }

 

}