Android:不推荐使用非滑动标签? [英] Android: non-sliding tabs are deprecated?

问题描述

我有一个非常简单的任务(至少我是这么认为的) - 制作 5 个不可滚动的静态标签，其中包含图标和片段

I have a very simple task (at least I thought so) - make a 5 non-scrollable static tabs with icons and fragments within

我花了一整天的时间来完成这项任务，我真的很惊讶，似乎在现代 Android API 中很难实现，因为我发现的所有东西都是无用的:

I had spent full day on this task and I really was surprised , it seems that in modern Android API's it's hard to implement, cause all that I had found are useless:

• PagerTabStrip - 它是可滚动的，不能使用固定数量的显示标签

• PagerTabStrip - it's scrollable, can't use a fixed count of displayed tabs

ActionBar.TabListener - 自 API 21 起已弃用

ActionBar.TabListener - deprecated since API 21

FragmentTabHost - 有一些错误渲染期间引发异常:没有标签已知为空标签"

FragmentTabHost - has some bug "Exception raised during rendering: No tab known for tag null"

SlidingTabLayout - 再次滑动 :( 不能使用固定数量的显示标签

SlidingTabLayout - sliding again :( can't use a fixed count of displayed tabs

也许我错过了什么?问候.

Maybe I've missed something? Regards.

推荐答案

正如我承诺的那样，我为你做了一些演示项目.

As I promised I made some demo project for you.

对你的问题最简单的解决方案似乎是 LinearLayout，这就是我使用的，也是 android 的图像.

The most simple solution for you problem seemed LinearLayout and that is what I used and also the android's images.

首先，您需要在名为 attrs.xml 的 values 文件夹中创建一个文件.如果您已经拥有它，那么只需添加样式

First you need to create a file in values folder named attrs.xml. If you already have it then just add the stylable

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="SimpleTabIndicator">
        <attr name="numberOfTabs" format="integer"/>
        <attr name="indicatorColor" format="color"/>
    </declare-styleable>
</resources>

然后创建一个名为SimpleTabIndicator

import android.content.Context;
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.os.Build;
import android.util.AttributeSet;
import android.view.View;


public class SimpleTabIndicator extends View {

    private static final String TAG = SimpleTabIndicator.class.getSimpleName();

    private float density;

    private int measuredHeight, measuredWidth;
    private int mNumberOfTabs;

    private Paint mIndicatorPaint;
    private int mIndicatorColor = 0xFFFDE992;
    private int currentTab = 1;


    public SimpleTabIndicator(Context context) {
        super(context);
        init(null, 0);
    }

    public SimpleTabIndicator(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(attrs, 0);
    }

    public SimpleTabIndicator(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(attrs, defStyleAttr);
    }


    private void init(AttributeSet attrs, int style) {

        if (!isInEditMode() && Build.VERSION.SDK_INT >= 11) {
            setLayerType(View.LAYER_TYPE_NONE, null);
        }

        Resources res = getResources();
        density = res.getDisplayMetrics().density;
        TypedArray typedArray = getContext().obtainStyledAttributes(attrs, R.styleable.SimpleTabIndicator, style, 0);

        mIndicatorColor = typedArray.getColor(R.styleable.SimpleTabIndicator_indicatorColor, mIndicatorColor);
        mNumberOfTabs = typedArray.getInt(R.styleable.SimpleTabIndicator_numberOfTabs, 1);

        typedArray.recycle();

        mIndicatorPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
        mIndicatorPaint.setStyle(Paint.Style.FILL);
        mIndicatorPaint.setColor(mIndicatorColor);
    }

    public int getNumberOfTabs() {
        return mNumberOfTabs;
    }

    public void setNumberOfTabs(int mNumberOfTabs) {
        this.mNumberOfTabs = mNumberOfTabs;
        invalidate();
    }

    public int getCurrentTab() {
        return currentTab;
    }

    public void setCurrentTab(int currentTab) {
        this.currentTab = currentTab;
        invalidate();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

        measuredHeight = getDefaultSize(getSuggestedMinimumHeight(), heightMeasureSpec);
        measuredWidth = getDefaultSize(getSuggestedMinimumWidth(), widthMeasureSpec);

        setMeasuredDimension(measuredWidth, measuredHeight);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        if (measuredHeight <= 0 || measuredWidth <= 0 || mNumberOfTabs == 0) {
            return; // Not much we can draw :(
        }

        int length = measuredWidth / mNumberOfTabs;
        int startX = (currentTab - 1) * length;

        canvas.drawRect(startX, 0, startX + length, measuredHeight, mIndicatorPaint);
    }


}

接下来是 ZoomOutPageTransformer.这家伙是从谷歌借来的".

Next up is the ZoomOutPageTransformer. This guy is "borrowed" from Google.

import android.support.v4.view.ViewPager;
import android.view.View;

public class ZoomOutPageTransformer implements ViewPager.PageTransformer {
    private static final float MIN_SCALE = 0.85f;
    private static final float MIN_ALPHA = 0.5f;

    public void transformPage(View view, float position) {
        int pageWidth = view.getWidth();
        int pageHeight = view.getHeight();

        if (position < -1) { // [-Infinity,-1)
            // This page is way off-screen to the left.
            view.setAlpha(0);

        }
        else if (position <= 1) { // [-1,1]
            // Modify the default slide transition to shrink the page as well
            float scaleFactor = Math.max(MIN_SCALE, 1 - Math.abs(position));
            float vertMargin = pageHeight * (1 - scaleFactor) / 2;
            float horzMargin = pageWidth * (1 - scaleFactor) / 2;
            if (position < 0) {
                view.setTranslationX(horzMargin - vertMargin / 2);
            }
            else {
                view.setTranslationX(-horzMargin + vertMargin / 2);
            }

            // Scale the page down (between MIN_SCALE and 1)
            view.setScaleX(scaleFactor);
            view.setScaleY(scaleFactor);

            // Fade the page relative to its size.
            view.setAlpha(MIN_ALPHA + (scaleFactor - MIN_SCALE) / (1 - MIN_SCALE) * (1 - MIN_ALPHA));

        }
        else { // (1,+Infinity]
            // This page is way off-screen to the right.
            view.setAlpha(0);
        }
    }
}

接下来制作一个名为 dummy_fragment_layout.xml

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/fragmentNumber"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_centerVertical="true"
        android:gravity="center_horizontal"
        android:text="1"
        android:textSize="50sp"
        android:textStyle="bold"/>

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_above="@id/fragmentNumber"
        android:gravity="center_horizontal"
        android:text="Fragment"
        android:textSize="30sp"/>
</RelativeLayout>

现在主要活动activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#808080"
    android:orientation="vertical"
    >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="?actionBarSize"
        android:background="#26292E"
        android:orientation="horizontal">

        <ImageView
            android:id="@+id/tab1"
            android:layout_width="0dip"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:adjustViewBounds="true"
            android:onClick="onTabSelected"
            android:padding="10dp"
            android:src="@android:drawable/btn_radio"
            android:tag="1"/>

        <ImageView
            android:id="@+id/tab2"
            android:layout_width="0dip"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:adjustViewBounds="true"
            android:onClick="onTabSelected"
            android:padding="10dp"
            android:src="@android:drawable/btn_star"
            android:tag="2"/>

        <ImageView
            android:id="@+id/tab3"
            android:layout_width="0dip"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:adjustViewBounds="true"
            android:onClick="onTabSelected"
            android:padding="10dp"
            android:src="@android:drawable/btn_star"
            android:tag="3"/>

        <ImageView
            android:id="@+id/tab4"
            android:layout_width="0dip"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:adjustViewBounds="true"
            android:onClick="onTabSelected"
            android:padding="10dp"
            android:src="@android:drawable/btn_star"
            android:tag="4"/>

        <ImageView
            android:id="@+id/tab5"
            android:layout_width="0dip"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:adjustViewBounds="true"
            android:onClick="onTabSelected"
            android:padding="10dp"
            android:src="@android:drawable/btn_star"
            android:tag="5"/>


    </LinearLayout>

    <test.kseneman.si.test.SimpleTabIndicator
        android:id="@+id/tabIndicator"
        android:layout_width="match_parent"
        android:layout_height="2dp"
        android:background="#26292E"
        app:indicatorColor="#FFFDE992"
        app:numberOfTabs="5"/>

    <android.support.v4.view.ViewPager
        android:id="@+id/pager"
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

</LinearLayout>

最后是 MainActivity

And finally the MainActivity

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentStatePagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.ActionBarActivity;
import android.util.Log;
import android.view.View;
import android.widget.ImageView;


public class MainActivity extends ActionBarActivity {

    private ViewPager mPager;
    private DummyFragmentsAdapter mPagerAdapter;
    private SimpleTabIndicator tabIndicator;
    private ImageView selectedImageView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mPagerAdapter = new DummyFragmentsAdapter(getSupportFragmentManager());
        tabIndicator = (SimpleTabIndicator) findViewById(R.id.tabIndicator);

        // Default state
        selectedImageView = (ImageView) findViewById(R.id.tab1);

        mPager = (ViewPager) findViewById(R.id.pager);
        mPager.setAdapter(mPagerAdapter);
        mPager.setPageTransformer(false, new ZoomOutPageTransformer());
    }

    public void onTabSelected(View v) {

        // Sanity check
        if (v == null || !(v instanceof ImageView) || v.getTag() == null) {
            return;
        }

        int postion = Integer.valueOf((String) v.getTag());
        Log.d("onTabSelected", "postion: " + postion);

        if (postion == mPager.getCurrentItem() + 1) {
            // The same selected, do nothing?
            return;
        }

        // Change selected images
        selectedImageView.setImageResource(android.R.drawable.btn_star);
        selectedImageView = (ImageView) v;
        selectedImageView.setImageResource(android.R.drawable.btn_radio);

        mPager.setCurrentItem(postion - 1); // They start at 0
        tabIndicator.setCurrentTab(postion);
    }

    private class DummyFragmentsAdapter extends FragmentStatePagerAdapter {

        public DummyFragmentsAdapter(FragmentManager fm) {
            super(fm);
        }

        @Override
        public Fragment getItem(int position) {
            DummyFragment fragment = new DummyFragment();
            Bundle b = new Bundle();
            b.putInt(DummyFragment.EXTRA_FRAGMENT_NUMBER, position);
            fragment.setArguments(b);
            return fragment;
        }

        @Override
        public int getCount() {
            return 5;
        }
    }
}

提供完整的项目 zip 这里

A complete project zip is available here

这是它的样子

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