Add the FloatingActionButtonBuilder class

library/src/main/java/com/github/clans/fab/FloatingActionButtonBuilder.java

@@ -0,0 +1,216 @@
+package com.github.clans.fab;
+
+import android.app.Activity;
+import android.graphics.drawable.Drawable;
+import android.util.DisplayMetrics;
+import android.util.TypedValue;
+import android.view.Gravity;
+import android.view.ViewGroup;
+import android.widget.FrameLayout;
+import android.widget.FrameLayout.LayoutParams;
+
+/**
+ * The <code>FloatingActionButtonBuilder</code> helps you construct easily a
+ * {@link #FloatingActionButton} directly from your activity (no xml resource
+ * invocation).<br>
+ * <br>
+ * Example:
+ * <br>
+ * <br>
+ * <b><code>FloatingActionButtonBuilder builder = new FloatingActionButtonBuilder(this);</code></b><br>
+ * <b><code>builder.setSize(56);</code></b><br>
+ * <b><code>builder.setColorNormal(colorNormal);</code></b><br>
+ * <b><code>builder.setColorPressed(colorPressed);</code></b><br>
+ * <b><code>builder.setColorRipple(colorRipple);</code></b><br>
+ * <b><code>builder.setDrawable(getResources().getDrawable(R.drawable.ic_add_white_24dp));</code></b><br>
+ * <b><code>builder.setElevation(4);</code></b><br>
+ * <b><code>builder.setMargins(0, 0, bottomEndMargins, bottomEndMargins);</code></b><br>
+ * <b><code>FloatingActionButton fab = builder.build();</code></b><br>
+ * <b><code>fab.setOnClickListener(this);</code></b><br>
+ * 
+ * @author Erkan Molla
+ * @version 1.0.0
+ */
+public class FloatingActionButtonBuilder {
+
+    private final Activity       mActivity;
+    private final DisplayMetrics mDisplayMetrics;
+    private LayoutParams         mLayoutParams = null;
+    private int                  mGravity      = Gravity.BOTTOM | Gravity.END;
+    private Drawable             mDrawable     = null;
+    private int                  mColorNormal  = 0;
+    private int                  mColorPressed = 0;
+    private int                  mColorRipple  = 0;
+    private float                mElevation    = 0;
+
+    /**
+     * Initialize the builder class with your activity as parameter.
+     * 
+     * @param context The activity that is calling this constructor
+     */
+    public FloatingActionButtonBuilder(final Activity context) {
+        mActivity = context;
+        mDisplayMetrics = context.getResources().getDisplayMetrics();
+    }
+
+    /**
+     * Sets the size in dp.
+     * 
+     * @param dp density-independent pixel
+     * @return this
+     * @see <a
+     *      href="http://developer.android.com/guide/practices/screens_support.html">Supporting
+     *      Multiple Screens</a>
+     */
+    public FloatingActionButtonBuilder setSize(final int dp) {
+        int px = (int) toPixel(dp);
+        mLayoutParams = new FrameLayout.LayoutParams(px, px);
+        return this;
+    }
+
+    /**
+     * Sets the gravity.
+     * 
+     * @param gravity to be set
+     * @return this
+     * @see <a
+     *      href="http://developer.android.com/reference/android/view/Gravity.html">Gravity</a>
+     */
+    public FloatingActionButtonBuilder setGravity(final int gravity) {
+        mGravity = gravity;
+        return this;
+    }
+
+    /**
+     * Sets the margins in dp.
+     * 
+     * @param left the left margin size
+     * @param top the top margin size
+     * @param right the right margin size
+     * @param bottom the bottom margin size
+     * @return this
+     */
+    public FloatingActionButtonBuilder setMargins(final int left, final int top, final int right,
+            final int bottom) {
+        int leftPx = (int) toPixel(left);
+        int topPx = (int) toPixel(top);
+        int rightPx = (int) toPixel(right);
+        int bottomPx = (int) toPixel(bottom);
+        mLayoutParams.setMargins(leftPx, topPx, rightPx, bottomPx);
+        return this;
+    }
+
+    /**
+     * Sets the drawable.
+     * 
+     * @param drawable to be set
+     * @return this
+     */
+    public FloatingActionButtonBuilder setDrawable(final Drawable drawable) {
+        mDrawable = drawable;
+        return this;
+    }
+
+    /**
+     * Sets the normal, pressed and ripple colors.
+     * 
+     * @param colorNormal normal color
+     * @param colorPressed pressed color
+     * @param colorRipple ripple color
+     * @return this
+     */
+    public FloatingActionButtonBuilder setColors(final int colorNormal, final int colorPressed,
+            final int colorRipple) {
+        mColorNormal = colorNormal;
+        mColorPressed = colorPressed;
+        mColorRipple = colorRipple;
+        return this;
+    }
+
+    /**
+     * Sets the normal color.
+     * 
+     * @param colorNormal normal color
+     * @return this
+     */
+    public FloatingActionButtonBuilder setColorNormal(final int colorNormal) {
+        mColorNormal = colorNormal;
+        return this;
+    }
+
+    /**
+     * Sets the pressed color.
+     * 
+     * @param colorPressed pressed color
+     * @return this
+     */
+    public FloatingActionButtonBuilder setColorPressed(final int colorPressed) {
+        mColorPressed = colorPressed;
+        return this;
+    }
+
+    /**
+     * Sets the ripple color.
+     * 
+     * @param colorRipple ripple color
+     * @return this
+     */
+    public FloatingActionButtonBuilder setColorRipple(final int colorRipple) {
+        mColorRipple = colorRipple;
+        return this;
+    }
+
+    /**
+     * Sets the elevation in dp.
+     * 
+     * @param dp elevation to be applied
+     * @return this
+     */
+    public FloatingActionButtonBuilder setElevation(final int dp) {
+        mElevation = toPixel(dp);
+        return this;
+    }
+
+    /**
+     * Builds the <code>FloatingActionButton</code> with all specified
+     * parameters.
+     * 
+     * @return a <code>FloatingActionButton</code> as requested
+     */
+    public FloatingActionButton build() {
+        final FloatingActionButton fab = new FloatingActionButton(mActivity);
+        fab.setButtonSize(FloatingActionButton.SIZE_NORMAL);
+        fab.setImageDrawable(mDrawable);
+        fab.setColors(mColorNormal, mColorPressed, mColorRipple);
+        fab.setElevationCompat(mElevation);
+        mLayoutParams.gravity = mGravity;
+        ViewGroup root = (ViewGroup) mActivity.findViewById(android.R.id.content);
+        root.addView(fab, mLayoutParams);
+        return fab;
+    }
+
+    /**
+     * The calculation (dp * scale + 0.5f) is a widely used to convert dp to
+     * pixel units based on density scale.
+     * 
+     * @param dp density-independent pixel
+     * @param scale the logical density of the display
+     * @return the pixel value
+     * @see <a href=
+     *      "http://developer.android.com/guide/practices/screens_support.html#dips-pels"
+     *      >Converting dp units to pixel units</a>
+     */
+    public int toPixel(int dp, float scale) {
+        return (int) (dp * scale + 0.5f);
+    }
+
+    /**
+     * Converts the given dp value to pixels.
+     * 
+     * @param dp density-independent pixel
+     * @return pixels of the given dp
+     */
+    public float toPixel(final int dp) {
+        return TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, mDisplayMetrics);
+    }
+}