如图，直线\(y=kx+b\)分别与\(x\)轴、\(y\)轴交于点\(A(2,0)\)和点\(B\)，直线\(y=x+1\)分别与\(x\)轴、\(y\)轴交于点\(C\)和点\(D\)，两直线交于第一象限内的点\(E\)，并且点\(D\)为\(CE\)的中点．
\((1)\)求直线\(y=kx+b\)的解析式；
\((2)\)过点\(D\)作\(DF/\!/x\)轴，交直线\(y=kx+b\)于点\(F\)，则\(\triangle DEF\)的面积为 ______ ．