Android开发笔记-ch3.2.10 Scroll, 3.2.11 Theme, Color and Style, 3.2.12 CardView, RecycleView and Coverflow

3.2.10 Scroll

Refer this SO for some discussion about multi-line TextView. Some argues that android:inputType="textMultiLine" is for EditView but may work for TextView. For scroll TextView, refer to this SO, might(some say no) need to set android:scrollbars = "vertical" and android:maxLines and add this in code: myTextView.setMovementMethod(new ScrollingMovementMethod());

Other suggestion is to embed the TextView into ScrollView, just do NOT specify android:layout_height="fill_parent"

A cool feature in Cheesesquare sample is auto hide or show app bar with scroll event. Refer to AppBarLayout, SO, CoordinatorLayout: it is all in layout xml, first add this for the android.support.v7.widget.Toolbar: app:layout_scrollFlags="scroll|enterAlways|snap"

Second, add this to all nested view: app:layout_behavior="@string/appbar_scrolling_view_behavior". This works with RecyclerView, but not with TextView. One way is to put the TextView inside a NestScrollView as below, and no need calling setMovementMethod for scroll:

<android.support.v4.widget.NestedScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    app:layout_behavior="@string/appbar_scrolling_view_behavior">
<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView
          android:id="@+id/tvInfo"
          android:layout_width="match_parent"

Refer to this SO for ScrollView inside another ScrollView. Should never use a HorizontalScrollView with a ListView.

3.2.11 Theme, Color and Style

Here are some good guide:

https://www.google.com/design/spec/style/color.html

http://developer.android.com/training/material/theme.html

http://developer.android.com/guide/topics/ui/themes.html

http://www.google.com/design/spec/style/typography.html

Right shows three themes: Holo Dark, Holo Light and Holo Light with Dark Bar. This can be changed later by modifying res/values/styles.xml and res/values-vXX/styles.xml, or change app style directly in manifest file like this: android:theme="@android:style/Theme.Black"

A reference of all available styles in R.style and v7 R.style class.

For changing style of spinner, this SO is old and might be out-date. Refer to spinner. Set android:popupBackground in layout xml of Spinner to config the background does take effect. But set android:spinnerItemStyle doesn't work, might because code:

mAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
mAdapter = new ArrayAdapter<>(this, android.R.layout.simple_spinner_item);

Refer to R.layout and simple_spinner_dropdown_item.xml: style="?android:attr/spinnerDropDownItemStyle"

This SO mentioned you can override android:dropDownSpinnerStyle, android:spinnerDropDownItemStyle, and even android:dropDownListViewStyle attribute of the theme, but no detail how.

Method from this post does work, the xml files should be put under layout. Little issue with the simple_spinner_item.xml line:

android:layout_height="?android:attr/dropdownListPreferredItemHeight" is causing error: Attribute is not public. To solve this problem, refer to SO and SO, or change it to "?android:attr/listPreferredItemHeight", which has too big gap. But change to “wrap_content” make it too tight. Remove “?android:” is just fine for me. Then to change the size and color of the text, add this

android:textSize="14sp" and android:textColor="#ffffff" to both xml and it works perfect with small white text.

3.2.12 CardView, RecycleView and Coverflow

For CoverFlow, refer to this SO. As it mentioned, the close one is the Gallery widget. Two code are availabe at:

http://www.inter-fuser.com/2010/01/android-coverflow-widget.html which is a little old(2010), and

http://code.google.com/p/android-coverflow/ which is based on above one.