Question

我正在使用viewPager和android.support.design.widget.TabLayout。我的xml是

<RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <android.support.v4.view.ViewPager
            android:id="@+id/home_container"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_marginBottom="@dimen/custom_tab_layout_height"
            app:layout_behavior="@string/appbar_scrolling_view_behavior" />

        <!-- tabs -->
        <android.support.design.widget.TabLayout
            android:id="@+id/home_tabs"
            android:layout_width="match_parent"
            android:layout_height="@dimen/custom_tab_layout_height"
            android:layout_alignParentBottom="true"
            app:tabGravity="fill"
            android:background="@color/light_blue_low_opacity"
            app:tabIndicatorHeight="0dp"
            app:tabMode="fixed"
            app:tabPaddingEnd="0dp"
            app:tabPaddingStart="0dp"
            app:tabSelectedTextColor="@color/light_green"
            app:tabTextAppearance="@style/HomeTabsTextAppearance"
            app:tabTextColor="@color/white" />

    </RelativeLayout>

我将viewPager设置如下

 mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

        mViewPager = (ViewPager) findViewById(R.id.home_container);
        mViewPager.setAdapter(mSectionsPagerAdapter);
        mViewPager.setPagingEnabled(false);
        mViewPager.setOffscreenPageLimit(5);

        tabLayout = (TabLayout) findViewById(R.id.home_tabs);
        tabLayout.setTabTextColors(ContextCompat.getColorStateList(this, R.color.color_home_tabs));
        tabLayout.setupWithViewPager(mViewPager);

我的tabListener是

 tabLayout.setOnTabSelectedListener(
                new TabLayout.ViewPagerOnTabSelectedListener(mViewPager) {
                    @Override
                    public void onTabSelected(TabLayout.Tab tab) {
                        super.onTabSelected(tab);
                        int position = tab.getPosition();
                    mViewPager.setCurrentItem(position);

                    String tab0TextUnSelected = "<font color='" + ContextCompat.getColor(getApplicationContext(), R.color.white) + "'> " + getResources().getString(R.string.home_tab1) + " </font>";
                    String tab1TextUnSelected = "<font color='" + ContextCompat.getColor(getApplicationContext(), R.color.white) + "'> " + getResources().getString(R.string.home_tab2) + "</font>";
                    String tab2TextUnSelected = "<font color='" + ContextCompat.getColor(getApplicationContext(), R.color.white) + "'> " + getResources().getString(R.string.home_tab3) + "</font>";
                    String tab3TextUnSelected = "<font color='" + ContextCompat.getColor(getApplicationContext(), R.color.white) + "'> " + getResources().getString(R.string.home_tab4) + "</font>";
                    String tab4TextUnSelected = "<font color='" + ContextCompat.getColor(getApplicationContext(), R.color.white) + "'> " + getResources().getString(R.string.home_tab5) + "</font>";


                    String tab0TextSelected = "<font color='" + ContextCompat.getColor(getApplicationContext(), R.color.light_green) + "'> " + getResources().getString(R.string.home_tab1) + " </font>";
                    String tab1TextSelected = "<font color='" + ContextCompat.getColor(getApplicationContext(), R.color.light_green) + "'> " + getResources().getString(R.string.home_tab2) + "</font>";
                    String tab2TextSelected = "<font color='" + ContextCompat.getColor(getApplicationContext(), R.color.light_green) + "'> " + getResources().getString(R.string.home_tab3) + "</font>";
                    String tab3TextSelected = "<font color='" + ContextCompat.getColor(getApplicationContext(), R.color.light_green) + "'> " + getResources().getString(R.string.home_tab4) + "</font>";
                    String tab4TextSelected = "<font color='" + ContextCompat.getColor(getApplicationContext(), R.color.light_green) + "'> " + getResources().getString(R.string.home_tab5) + "</font>";

                    TabLayout.Tab tab0 = tabLayout.getTabAt(0);
                    TabLayout.Tab tab1 = tabLayout.getTabAt(1);
                    TabLayout.Tab tab2 = tabLayout.getTabAt(2);
                    TabLayout.Tab tab3 = tabLayout.getTabAt(3);
                    TabLayout.Tab tab4 = tabLayout.getTabAt(4);


                    if (tab0 != null) {
                        tab0.setIcon(R.drawable.ic_home_profile_unselected);
                        tab0.setText(Html.fromHtml(tab0TextUnSelected));
                    }

                    if (tab1 != null) {
                        tab1.setIcon(R.drawable.ic_home_rewards_unselected);
                        tab1.setText(Html.fromHtml(tab1TextUnSelected));
                    }

                    if (tab2 != null) {
                        tab2.setIcon(R.drawable.ic_home_gallups_unselected);
                        tab2.setText(Html.fromHtml(tab2TextUnSelected));
                    }

                    if (tab3 != null) {
                        tab3.setIcon(R.drawable.ic_home_statistics_unselected);
                        tab3.setText(Html.fromHtml(tab3TextUnSelected));
                    }

                    if (tab4 != null) {
                        tab4.setIcon(R.drawable.ic_home_settings_unselected);
                        tab4.setText(Html.fromHtml(tab4TextUnSelected));
                    }

                    if (position == 0) {
                        if (tab0 != null) {
                            tab0.setIcon(R.drawable.ic_home_profile_selected);
                            tab0.setText(Html.fromHtml(tab0TextSelected));
                        }
                    } else if (position == 1) {
                        if (tab1 != null) {
                            tab1.setIcon(R.drawable.ic_home_rewards_selected);
                            tab1.setText(Html.fromHtml(tab1TextSelected));
                        }
                    } else if (position == 2) {
                        if (tab2 != null) {
                            tab2.setIcon(R.drawable.ic_home_gallups_selected);
                            tab2.setText(Html.fromHtml(tab2TextSelected));
                        }
                    } else if (position == 3) {
                        if (tab3 != null) {
                            tab3.setIcon(R.drawable.ic_home_statistics_selected);
                            tab3.setText(Html.fromHtml(tab3TextSelected));
                        }
                    } else if (position == 4) {
                        if (tab4 != null) {
                            tab4.setIcon(R.drawable.ic_home_settings_selected);
                            tab4.setText(Html.fromHtml(tab4TextSelected));
                        }
                    }

                }


            });

我已覆盖onBackPressed方法，如下所示

 if (mViewPager.getCurrentItem() != 0) {
     mViewPager.setCurrentItem(mViewPager.getCurrentItem() - 1, true);
}

总而言之，我有图标和文字标签。选择选项卡后，图标将更改，文本将变为绿色。取消选择选项卡后，图标将更改，文本将变为白色。当用户单击选项卡时，这很好用。当用户单击后退按钮时，图标和文本颜色会正确更改，但对于上一个选项卡，文本仍保持绿色。

Answer 1

试试这个，

@Override
    public void onBackPressed() {

        if (viewPager.getCurrentItem() != 0) {
            viewPager.setCurrentItem(viewPager.getCurrentItem() - 1,false);
        }else{
             finish();
        }

    }

但不要调用super.onBackPressed（）方法。

Answer 2

不确定我是否正确理解了您的问题，但请尝试致电

super.onBackPressed();

在您if陈述之后

。

Answer 3

您的ViewPager需要一个OnPageChangeListener来更改选定的标签。

    mViewPager.setOnPageChangeListener(
        new ViewPager.SimpleOnPageChangeListener() {
            @Override
            public void onPageSelected(int position) {
                // When swiping between pages, select the
                // corresponding tab.
                getActionBar().setSelectedNavigationItem(position);
            }
        });
...

Answer 4

使用以下代码覆盖onBackPressed()的{{1}}方法：

Activity

后退按钮和ViewPager

4 个答案: