/*
* Copyright (C) 2008 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 android.util;
import com.google.android.collect.Lists;
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.ScrollView;
import android.widget.TextView;
import java.util.List;
/**
* Utility base class for creating scroll view scenarios, allowing you to add
* a series of different kinds of views arranged vertically, taking up a
* specified amount of the screen height.
*/
public abstract class ScrollViewScenario extends Activity {
/**
* Holds content of scroll view
*/
private LinearLayout mLinearLayout;
/**
* The actual scroll view
*/
private ScrollView mScrollView;
/**
* What we need of each view that the user wants: the view, and the ratio
* to the screen height for its desired height.
*/
private interface ViewFactory {
View create(final Context context);
float getHeightRatio();
}
/**
* Partially implement ViewFactory given a height ratio.
* A negative height ratio means that WRAP_CONTENT will be used as height
*/
private static abstract class ViewFactoryBase implements ViewFactory {
private float mHeightRatio;
@SuppressWarnings({"UnusedDeclaration"})
private ViewFactoryBase() {throw new UnsupportedOperationException("don't call this!");}
protected ViewFactoryBase(float heightRatio) {
mHeightRatio = heightRatio;
}
public float getHeightRatio() {
return mHeightRatio;
}
}
/**
* Builder for selecting the views to be vertically arranged in the scroll
* view.
*/
@SuppressWarnings({"JavaDoc"})
public static class Params {
List<ViewFactory> mViewFactories = Lists.newArrayList();
int mTopPadding = 0;
int mBottomPadding = 0;
/**
* Add a text view.
* @param text The text of the text view.
* @param heightRatio The view's height will be this * the screen height.
*/
public Params addTextView(final String text, float heightRatio) {
mViewFactories.add(new ViewFactoryBase(heightRatio) {
public View create(final Context context) {
final TextView tv = new TextView(context);
tv.setText(text);
return tv;
}
});
return this;
}
/**
* Add multiple text views.
* @param numViews the number of views to add.
* @param textPrefix The text to prepend to each text view.
* @param heightRatio The view's height will be this * the screen height.
*/
public Params addTextViews(int numViews, String textPrefix, float heightRatio) {
for (int i = 0; i < numViews; i++) {
addTextView(textPrefix + i, heightRatio);
}
return this;
}
/**
* Add a button.
* @param text The text of the button.
* @param heightRatio The view's height will be this * the screen height.
*/
public Params addButton(final String text, float heightRatio) {
mViewFactories.add(new ViewFactoryBase(heightRatio) {
public View create(final Context context) {
final Button button = new Button(context);
button.setText(text);
return button;
}
});
return this;
}
/**
* Add multiple buttons.
* @param numButtons the number of views to add.
* @param textPrefix The text to prepend to each button.
* @param heightRatio The view's height will be this * the screen height.
*/
public Params addButtons(int numButtons, String textPrefix, float heightRatio) {
for (int i = 0; i < numButtons; i++) {
addButton(textPrefix + i, heightRatio);
}
return this;
}
/**
* Add an {@link InternalSelectionView}.
* @param numRows The number of rows in the internal selection view.
* @param heightRatio The view's height will be this * the screen height.
*/
public Params addInternalSelectionView(final int numRows, float heightRatio) {
mViewFactories.add(new ViewFactoryBase(heightRatio) {
public View create(final Context context) {
return new InternalSelectionView(context, numRows, "isv");
}
});
return this;
}
/**
* Add a sublayout of buttons as a single child of the scroll view.
* @param numButtons The number of buttons in the sub layout
* @param heightRatio The layout's height will be this * the screen height.
*/
public Params addVerticalLLOfButtons(final String prefix, final int numButtons, float heightRatio) {
mViewFactories.add(new ViewFactoryBase(heightRatio) {
public View create(Context context) {
final LinearLayout ll = new LinearLayout(context);
ll.setOrientation(LinearLayout.VERTICAL);
// fill width, equally weighted on height
final LinearLayout.LayoutParams lp =
new LinearLayout.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT, 0, 1f);
for (int i = 0; i < numButtons; i++) {
final Button button = new Button(context);
button.setText(prefix + i);
ll.addView(button, lp);
}
return ll;
}
});
return this;
}
public Params addPaddingToScrollView(int topPadding, int bottomPadding) {
mTopPadding = topPadding;
mBottomPadding = bottomPadding;
return this;
}
}
/**
* Override this and initialized the views in the scroll view.
* @param params Used to configure the contents of the scroll view.
*/
protected abstract void init(Params params);
public LinearLayout getLinearLayout() {
return mLinearLayout;
}
public ScrollView getScrollView() {
return mScrollView;
}
/**
* Get the child contained within the vertical linear layout of the
* scroll view.
* @param index The index within the linear layout.
* @return the child within the vertical linear layout of the scroll view
* at the specified index.
*/
@SuppressWarnings({"unchecked"})
public <T extends View> T getContentChildAt(int index) {
return (T) mLinearLayout.getChildAt(index);
}
/**
* Hook for changing how scroll view's are created.
*/
@SuppressWarnings({"JavaDoc"})
protected ScrollView createScrollView() {
return new ScrollView(this);
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// for test stability, turn off title bar
requestWindowFeature(Window.FEATURE_NO_TITLE);
int screenHeight = getWindowManager().getDefaultDisplay().getHeight()
- 25;
mLinearLayout = new LinearLayout(this);
mLinearLayout.setOrientation(LinearLayout.VERTICAL);
// initialize params
final Params params = new Params();
init(params);
// create views specified by params
for (ViewFactory viewFactory : params.mViewFactories) {
int height = ViewGroup.LayoutParams.WRAP_CONTENT;
if (viewFactory.getHeightRatio() >= 0) {
height = (int) (viewFactory.getHeightRatio() * screenHeight);
}
final LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT, height);
mLinearLayout.addView(viewFactory.create(this), lp);
}
mScrollView = createScrollView();
mScrollView.setPadding(0, params.mTopPadding, 0, params.mBottomPadding);
mScrollView.addView(mLinearLayout, new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.MATCH_PARENT));
// no animation to speed up tests
mScrollView.setSmoothScrollingEnabled(false);
setContentView(mScrollView);
}
}
