解决微信分享图片太大无法分享和出现黑框问题，优化界面

app/src/main/java/com/gh/common/util/ShareUtils.java

@@ -4,7 +4,9 @@ import android.app.Activity;
 import android.content.ClipboardManager;
 import android.content.Context;
 import android.graphics.Bitmap;
+import android.graphics.Canvas;
 import android.graphics.Color;
+import android.graphics.Matrix;
 import android.os.Bundle;
 import android.support.v7.widget.GridLayoutManager;
 import android.support.v7.widget.RecyclerView;
@@ -34,6 +36,7 @@ import com.tencent.tauth.IUiListener;
 import com.tencent.tauth.Tencent;
 import com.tencent.tauth.UiError;
 
+import java.io.ByteArrayOutputStream;
 import java.util.ArrayList;
 import java.util.HashMap;
 
@@ -455,7 +458,15 @@ public class ShareUtils {
 
             @Override
             public void onLoadingComplete(String s, View view, Bitmap bitmap) {
-                msg.thumbData = Util.bmpToByteArray(bitmap, false);
+                String imgType = shareIcon.substring(shareIcon.length() - 3);
+                Bitmap resultBp;
+                if ("png".equals(imgType)){
+                    resultBp = addBackGround(bitmap);
+                }else {
+                    resultBp = compressBitmap(bitmap);
+                }
+
+                msg.thumbData = Util.bmpToByteArray(resultBp, true);
                 api.sendReq(req);
             }
 
@@ -466,4 +477,50 @@ public class ShareUtils {
         });
     }
 
+    //添加背景，防止图片格式为PNG的图片分享出现黑框问题
+    private Bitmap addBackGround(Bitmap result) {
+        Bitmap bgBitmap;
+        int[] colors = new int[result.getWidth()*result.getHeight()];
+        for (int i = 0; i < colors.length; i++) {
+            colors[i] = Color.WHITE;
+        }
+        bgBitmap = Bitmap.createBitmap(colors, result.getWidth(), result.getHeight(), Bitmap.Config.ARGB_8888);
+
+        Bitmap newmap = Bitmap
+                .createBitmap(result.getWidth(), result.getHeight(), Bitmap.Config.ARGB_8888);
+        Canvas canvas = new Canvas(newmap);
+        canvas.drawBitmap(bgBitmap, 0, 0, null);
+        canvas.drawBitmap(result, (result.getHeight() - result.getWidth()) / 2,
+                (result.getHeight() - result.getWidth()) / 2, null);
+        canvas.save(Canvas.ALL_SAVE_FLAG);
+        canvas.restore();
+        return newmap;
+    }
+
+    //压缩图片
+    private Bitmap compressBitmap(Bitmap bitmap) {
+        ByteArrayOutputStream bos = new ByteArrayOutputStream();
+        bitmap.compress(Bitmap.CompressFormat.JPEG, 85, bos);
+        float zoom = (float) Math.sqrt(10 * 1024 / (float) bos.toByteArray().length);
+
+        Matrix matrix = new Matrix();
+        matrix.setScale(zoom, zoom);
+
+        Bitmap result = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
+        bos.reset();
+
+        result.compress(Bitmap.CompressFormat.JPEG, 85, bos);
+
+        while(bos.toByteArray().length > 10 * 1024){
+            System.out.println(bos.toByteArray().length);
+            matrix.setScale(0.9f, 0.9f);
+            result = Bitmap.createBitmap(result, 0, 0, result.getWidth(), result.getHeight(), matrix, true);
+            bos.reset();
+            result.compress(Bitmap.CompressFormat.JPEG, 85, bos);
+
+        }
+
+        return result;
+    }
+
 }