Improve Gallery Detail

app/src/main/java/com/hippo/widget/SimpleGridLayout.java

@@ -0,0 +1,174 @@
+/*
+ * Copyright 2015 Hippo Seven
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.hippo.widget;
+
+import android.content.Context;
+import android.content.res.TypedArray;
+import android.util.AttributeSet;
+import android.view.View;
+import android.view.ViewGroup;
+
+import com.hippo.ehviewer.R;
+import com.hippo.yorozuya.MathUtils;
+import com.hippo.yorozuya.ViewUtils;
+
+/**
+ * not scrollable
+ *
+ * @author Hippo
+ *
+ */
+public class SimpleGridLayout extends ViewGroup {
+
+    private static final int DEFAULT_COLUMN_COUNT = 3;
+
+    private int mColumnCount;
+    private int mItemMargin;
+
+    private int[] mRowHeights;
+    private int mItemWidth;
+
+    public SimpleGridLayout(Context context) {
+        super(context);
+        init(context, null);
+    }
+
+    public SimpleGridLayout(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        init(context, attrs);
+    }
+
+    public SimpleGridLayout(Context context, AttributeSet attrs, int defStyle) {
+        super(context, attrs, defStyle);
+        init(context, attrs);
+    }
+
+    public void init(Context context, AttributeSet attrs) {
+        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.SimpleGridLayout);
+        mColumnCount = a.getInteger(R.styleable.SimpleGridLayout_columnCount, DEFAULT_COLUMN_COUNT);
+        mItemMargin = a.getDimensionPixelOffset(R.styleable.SimpleGridLayout_itemMargin, 0);
+        a.recycle();
+    }
+
+    public void setItemMargin(int itemMargin) {
+        if (mItemMargin != itemMargin) {
+            mItemMargin = itemMargin;
+            requestLayout();
+        }
+    }
+
+    public void setColumnCount(int columnCount) {
+        if (columnCount <= 0) {
+            throw new IllegalStateException("Column count can't be " + columnCount);
+        }
+
+        if (mColumnCount != columnCount) {
+            mColumnCount = columnCount;
+            requestLayout();
+        }
+    }
+
+    @Override
+    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+        int maxRowCount = MathUtils.ceilDivide(getChildCount(), mColumnCount);
+        if (mRowHeights == null || mRowHeights.length != maxRowCount) {
+            mRowHeights = new int[maxRowCount];
+        }
+
+        int widthMode = MeasureSpec.getMode(widthMeasureSpec);
+        int heightMode = MeasureSpec.getMode(heightMeasureSpec);
+        int maxWidth = MeasureSpec.getSize(widthMeasureSpec);
+        int maxHeight = MeasureSpec.getSize(heightMeasureSpec);
+
+        if (widthMode == MeasureSpec.UNSPECIFIED) {
+            maxWidth = 300;
+        }
+        if (heightMode == MeasureSpec.UNSPECIFIED) {
+            maxHeight = ViewUtils.MAX_SIZE;
+        }
+
+        // Get item width MeasureSpec
+        mItemWidth = Math.max(
+                (maxWidth - getPaddingLeft() - getPaddingRight() - ((mColumnCount - 1) * mItemMargin)) / mColumnCount, 1);
+        int itemWidthMeasureSpec = MeasureSpec.makeMeasureSpec(mItemWidth, MeasureSpec.EXACTLY);
+        int itemHeightMeasureSpec = MeasureSpec.UNSPECIFIED;
+
+        int measuredWidth = maxWidth;
+        int measuredHeight = 0;
+        int rowHeight = 0;
+        int row = 0;
+        int count = getChildCount();
+        for (int index = 0, indexInRow = 0; index < count; index++, indexInRow++) {
+            final View child = getChildAt(index);
+            if (child.getVisibility() == View.GONE) {
+                indexInRow--;
+                continue;
+            }
+
+            child.measure(itemWidthMeasureSpec, itemHeightMeasureSpec);
+
+            if (indexInRow == mColumnCount) {
+                // New row
+                indexInRow = 0;
+                rowHeight = 0;
+                row++;
+            }
+
+            rowHeight = Math.max(rowHeight, child.getMeasuredHeight());
+
+            if (indexInRow == mColumnCount - 1 || index == count - 1) {
+                mRowHeights[row] = rowHeight;
+                measuredHeight += rowHeight + mItemMargin;
+            }
+        }
+        measuredHeight -= mItemMargin;
+        measuredHeight = Math.max(0, Math.min(measuredHeight + getPaddingTop() + getPaddingBottom(), maxHeight));
+
+        setMeasuredDimension(measuredWidth, measuredHeight);
+    }
+
+    @Override
+    protected void onLayout(boolean changed, int l, int t, int r, int b) {
+        int itemWidth = mItemWidth;
+        int itemMargin = mItemMargin;
+        int paddingLeft = getPaddingLeft();
+        int left = paddingLeft;
+        int top = getPaddingTop();
+        int row = 0;
+        int count = getChildCount();
+        for (int index = 0, indexInRow = 0; index < count; index++, indexInRow++) {
+            final View child = getChildAt(index);
+            if (child.getVisibility() == View.GONE) {
+                indexInRow--;
+                continue;
+            }
+
+            if (indexInRow == mColumnCount) {
+                // New row
+                left = paddingLeft;
+                top += mRowHeights[row] + itemMargin;
+
+                indexInRow = 0;
+                row++;
+            }
+
+            child.layout(left, top, left + child.getMeasuredWidth(), top + child.getMeasuredHeight());
+
+            left += itemWidth + itemMargin;
+        }
+    }
+}