Add source

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

@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * 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.annotation.TargetApi;
+import android.content.Context;
+import android.graphics.Canvas;
+import android.os.Build;
+import android.util.AttributeSet;
+import android.view.View;
+
+/**
+ * Space is a lightweight View subclass that may be used to create gaps between components
+ * in general purpose layouts.
+ */
+public final class Space extends View {
+    /**
+     * {@inheritDoc}
+     */
+    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
+    public Space(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
+        super(context, attrs, defStyleAttr, defStyleRes);
+        if (getVisibility() == VISIBLE) {
+            setVisibility(INVISIBLE);
+        }
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public Space(Context context, AttributeSet attrs, int defStyleAttr) {
+        this(context, attrs, defStyleAttr, 0);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public Space(Context context, AttributeSet attrs) {
+        this(context, attrs, 0);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public Space(Context context) {
+        //noinspection NullableProblems
+        this(context, null);
+    }
+
+    /**
+     * Draw nothing.
+     *
+     * @param canvas an unused parameter.
+     */
+    @Override
+    public void draw(Canvas canvas) {
+    }
+
+    /**
+     * Compare to: {@link View#getDefaultSize(int, int)}
+     * If mode is AT_MOST, return the child size instead of the parent size
+     * (unless it is too big).
+     */
+    private static int getDefaultSize2(int size, int measureSpec) {
+        int result = size;
+        int specMode = MeasureSpec.getMode(measureSpec);
+        int specSize = MeasureSpec.getSize(measureSpec);
+
+        switch (specMode) {
+            case MeasureSpec.UNSPECIFIED:
+                result = size;
+                break;
+            case MeasureSpec.AT_MOST:
+                result = Math.min(size, specSize);
+                break;
+            case MeasureSpec.EXACTLY:
+                result = specSize;
+                break;
+        }
+        return result;
+    }
+
+    @Override
+    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+        setMeasuredDimension(
+                getDefaultSize2(getSuggestedMinimumWidth(), widthMeasureSpec),
+                getDefaultSize2(getSuggestedMinimumHeight(), heightMeasureSpec));
+    }
+}