如何创建三角形可绘制图形？

Question

I'm trying to draw a triangle shape in my XML layout .

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <rotate
            android:fromDegrees="45"
            android:pivotX="135%"
            android:pivotY="1%"
            android:toDegrees="45">
            <shape android:shape="rectangle">
                <solid android:color="@color/red" />
            </shape>
        </rotate>
    </item>
</layer-list>

My expectation is to build my drawable like below image's top right corner. I have to add this drawable in list item.

Answer 1

You can try this,

    <?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item >
        <rotate
            android:fromDegrees="-45"
            android:pivotX="0%"
            android:pivotY="-45%">
            <shape android:shape="rectangle">
                <solid android:color="#ff0" />
            </shape>
        </rotate>
    </item>
</layer-list>

example:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:layout_width="match_parent"
              android:layout_height="match_parent">

    <View
        android:layout_width="100dp"
        android:background="@drawable/ssampl"
        android:layout_height="100dp">

    </View>
</LinearLayout>

Answer 2

drawable-backround_triangle.xml

<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <rotate
            android:fromDegrees="45"
            android:toDegrees="45"
            android:pivotX="250%"
            android:pivotY="80%">
            <shape android:shape="rectangle">
                <solid android:color="@color/colorAccent" />
            </shape>
        </rotate>
    </item>
</layer-list>

then make your view as below example:

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView 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"
    app:cardCornerRadius="4dp"
    app:cardPreventCornerOverlap="false"
    app:cardUseCompatPadding="false">


    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@drawable/background_triangle">

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="horizontal"
            android:padding="@dimen/dp8"
            android:weightSum="1">

            <LinearLayout
                android:id="@+id/img_view"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentLeft="true"
                android:layout_centerVertical="true"
                android:gravity="center"
                android:orientation="vertical">

                <de.hdodenhof.circleimageview.CircleImageView
                    android:id="@+id/contact_img"
                    android:layout_width="120dp"
                    android:layout_height="120dp"
                    android:layout_gravity="center"
                    android:layout_marginTop="@dimen/dp8"
                    android:src="@drawable/ic_cars" />
            </LinearLayout>

            <RelativeLayout
                android:id="@+id/content_view"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_alignParentRight="true"
                android:layout_centerVertical="true"
                android:layout_marginLeft="@dimen/dp8"
                android:layout_toRightOf="@+id/img_view">

                <TextView
                    android:id="@+id/tv_request_status"
                    style="@style/txtview_standard_widget"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_alignParentTop="true"
                    android:layout_centerHorizontal="true"
                    android:layout_marginBottom="@dimen/dp8"
                    android:text="Pending"
                    android:textColor="@color/colorAccent" />

                <LinearLayout
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_below="@+id/tv_request_status"
                    android:orientation="vertical">

                    <LinearLayout
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:layout_marginLeft="@dimen/dp4"
                        android:layout_marginTop="@dimen/dp4"
                        android:weightSum="1">

                        <TextView
                            style="@style/txtview_standard_widget"
                            android:layout_width="0dp"
                            android:layout_height="wrap_content"
                            android:layout_weight="0.4"
                            android:text="Phone" />

                        <TextView
                            android:id="@+id/tv_phone_number"
                            style="@style/txtview_standard_widget"
                            android:layout_width="0dp"
                            android:layout_height="wrap_content"
                            android:layout_weight="0.6"
                            android:text="Phone" />
                    </LinearLayout>

                    <LinearLayout
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:layout_marginLeft="@dimen/dp4"
                        android:layout_marginTop="@dimen/dp4"
                        android:weightSum="1">

                        <TextView
                            style="@style/txtview_standard_widget"
                            android:layout_width="0dp"
                            android:layout_height="wrap_content"
                            android:layout_weight="0.4"
                            android:text="Email" />

                        <TextView
                            android:id="@+id/tv_email"
                            style="@style/txtview_standard_widget"
                            android:layout_width="0dp"
                            android:layout_height="wrap_content"
                            android:layout_weight="0.6"
                            android:text="joe@gmail.com" />
                    </LinearLayout>

                    <LinearLayout
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:layout_marginLeft="@dimen/dp4"
                        android:layout_marginTop="@dimen/dp4"
                        android:weightSum="1">

                        <TextView
                            style="@style/txtview_standard_widget"
                            android:layout_width="0dp"
                            android:layout_height="wrap_content"
                            android:layout_weight="0.4"
                            android:text="Age" />

                        <TextView
                            android:id="@+id/tv_age"
                            style="@style/txtview_standard_widget"
                            android:layout_width="0dp"
                            android:layout_height="wrap_content"
                            android:layout_weight="0.6"
                            android:text="Phone" />
                    </LinearLayout>

                    <LinearLayout
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:layout_marginLeft="4dp"
                        android:layout_marginTop="@dimen/dp4"
                        android:weightSum="1">

                        <TextView
                            style="@style/txtview_standard_widget"
                            android:layout_width="0dp"
                            android:layout_height="wrap_content"
                            android:layout_weight="0.4"
                            android:text="Gender" />

                        <TextView
                            android:id="@+id/tv_gender"
                            style="@style/txtview_standard_widget"
                            android:layout_width="0dp"
                            android:layout_height="wrap_content"
                            android:layout_weight="0.6"
                            android:text="Phone" />
                    </LinearLayout>

                    <LinearLayout
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:layout_marginLeft="@dimen/dp4"
                        android:layout_marginTop="@dimen/dp4"
                        android:weightSum="1">

                        <TextView
                            style="@style/txtview_standard_widget"
                            android:layout_width="0dp"
                            android:layout_height="wrap_content"
                            android:layout_weight="0.4"
                            android:text="Efficiency" />

                        <TextView
                            android:id="@+id/tv_efficiency"
                            style="@style/txtview_standard_widget"
                            android:layout_width="0dp"
                            android:layout_height="wrap_content"
                            android:layout_weight="0.6"
                            android:text="75%" />
                    </LinearLayout>
                </LinearLayout>
            </RelativeLayout>
        </RelativeLayout>
    </RelativeLayout>

</android.support.v7.widget.CardView>